"Ah, Elaine. Tis be a sweet day in Hell when you feel the fiery breath of my kiss on your lips and become my undead bride. I'll destroy any man who dares get in me way. Suffering sailors, tis good to be dead!"

Captain LeChuck is the primary villain and main catalyst of the Monkey Island series, setting in motion most of the events that make up the entire series and has always been directly or indirectly responsible for all the conflict in each game. Considered by many to be the most notorious and ruthless pirate to ever sail the seas, LeChuck was known for his cruelty and sadism in life and was obsessed with acquiring immense power through voodoo energy to conquer the Seven Seas. Establishing a reign of terror that took countless lives and immersing himself in the dark forces of voodoo in pursuit of power for decades, the pirate captain eventually met and became obsessed with Elaine Marley, the main heroine of the series, who rebuffed his advances, causing LeChuck's lust for power to become shared with an unhealthy fixation on Elaine and a desire to make her his unwilling, undead bride to assist him in his nefarious schemes and designs. Not willing to let Elaine elude his grasp, LeChuck began to make his plans to find the means to control the young woman, as well as the immense political power and influence she held over the Caribbean, for his own purposes.

To this end, LeChuck sacrificed what little humanity he had left and became a demonic, undead pirate, carrying over his lust and obsession for voodoo and Elaine Marley and reigned the seas as a feared and sadistic entity, forming numerous plans to abduct and marry Elaine and obtain ultimate voodoo powers to assume complete control over the seas. To accomplish these goals, the villain usually makes plans to build up an unstoppable demonic army and acquire rare voodoo treasures and artifacts, including the treasure of Big Whoop, the Ultimate Insult, and La Esponja Grande, to wield their incredible powers for his own ends. His plans to marry Elaine and conquer the seas are consistently foiled by Guybrush Threepwood, the main protganoist of the series, who soon becomes LeChuck's arch-nemesis due to his constant interference, culminating in a decade long battle between the two. Regardless of how many times he is defeated, LeChuck's evil is continuously reborn due to his perpetual desire to torment Guybrush and Elaine in increasingly grotesque incarnations including a ghost, zombie, and demon. The secrets to his death and demonic voodoo powers are revealed as well as much of his past throughout the series, making up the backbone for much of the events that have occurred before and throughout the series.

"Oh, that's just wonderful. I finally rid myself of twenty years of amnesia and the first thing I learn is that my granddaughter has married the sorriest excuse for a pirate in the seven seas. Someone get a coconut so I can go back to being blissfully ignorant."

Horatio Torquemeda Marley (also called Captain Marley, Grandpa Marley or H. T. Marley and later revealed to be the same person as Herman Toothrot) is a recurring character in the Monkey Island series. As Herman Toothrot he is the hermit of Monkey Island, although his tale of how he came to be on the island has been revised at least once. He makes appearances in the first four games, though his appearance in the third is more of a cameo (in the form of an electronic puppet on the Rollercoaster of Death).

In the fourth game Herman is revealed to be the grandfather of Elaine Marley, who until that point had been considered a separate character. This plot-twist is accompanied by a large retcon of the character's previous history which is at odds with previously established canon. Herman's character was initially based on Ben Gunn from Treasure Island.

"Hi, my name is Guybrush Threepwood and I want to be a pirate."

Guybrush Ulysses Marley-Threepwood is the protagonist and playable character in all five Monkey Island games by LucasArts. In the first game, The Secret of Monkey Island, Guybrush's goal is to become a pirate. Though he achieves this goal by completing the Three Trials, he never quite succeeds in becoming a true buccaneer, though his reputation would be carried throughout the seven seas for years on end. While initially driven by a lust for fame and fortune, Guyrbush's ambitions become much more complicated and clouded when he falls in love with the beautiful Elaine Marley, the governor of the Tri-Island area of the Caribbean. His love and infactuation with Elaine though soon makes Guybrush a target to the bloodthirsty and power crazed villain, LeChuck, who has his own plans to abduct and forcibly marry Elaine.

In the end, Guybrush would destroy LeChuck and win the heart of Elaine, though his love of adventures for greater fortunes would ensure that the naive pirate would get thrown into many more dangerous situations throughout his life as a pirate. With LeChuck returning several more times, each with a new plot for power over the seven seas and Elaine's hand in marriage, Guybrush soon becomes entangled in multiple quests to save those he loves and cares for and make up for his mistakes, allowing him to become a much more caring and noble person in the process. His continued victory over LeChuck and the constant dangers he puts himself into in order to save Elaine eventually convinces the young pirate governor to marry Guybrush. Ultimately, Guybrush goes from a selfish, self-serving individual driven by a lust for fame and wealth in the beginning of the series to a deeply caring individual who puts aside his own lusts for the love of his wife, Elaine, and saving her from LeChuck and his various plans by the end of the series.

"Oh, Guybrush. I know I shouldn't have anything to do with you, but there's something about your weakness and ineptitude that I find infectious."

Elaine Marley-Threepwood is the primary female-lead/damsel-in-distress in the Monkey Island series. Though she sometimes requires rescuing by the series' main character, Guybrush Threepwood, she is depicted as a confident, charming, and tough woman. She is constantly pursued by the undead pirate LeChuck, who never ceases to pursue her affections and attempts to turn her into his undead bride for his own self-serving purposes, but Elaine instead falls in love with the hapless Guybrush. Elaine is consistently kidnapped by LeChuck, prompting Guybrush to attempt a rescue, although Elaine is usually more than capable of escaping predicaments by herself. Over time she and Guybrush develop more of a co-operative method of handling problems; writer Michael Stemmle says that she has an "usual uncanny ability to think 23 moves ahead."

She is the former governor of the Tri-Island Area, which is comprised of Mêlée Island, Booty Island, and Plunder Island (but in Escape from Monkey Island appears to consist of several others including Lucre Island, where her family lawyers live and work). Though she resigned from her governing duties on Mêlée temporarily (having dumped Guybrush) she apparently retained her position by The Curse of Monkey Island. During her time in power, Elaine has two mansions, one on Mêlée and one on Booty, and a fortress on Plunder. She also had an unorganized array of assistants and personal guards that seemed incapable of protecting her from her various kidnappings. She eventually marries Guybrush and relinquishes her gubernatorial responsibilities to her grandfather, traveling with Guybrush to the fictional Gulf of Melange to cure the outbreak of a voodoo-empowered pox.

Elaine's first name is a reference to the 1967 film The Graduate. In initial development on The Secret of Monkey Island she was known simply as The Governor.

Stan (full name: Smilin' Stan S. Stanman) is one of the most frequently recurring characters in the Monkey Island series, having made appearances in all five games. He is a famously sleazy salesman who has run a number of disreputable businesses within the Tri-Island Area. Though he is never well-liked or particularly successful, Stan is eternally upbeat and confident.

"I am not your enemy Guybrush. In fact, I have most likely saved you from yourself." - The Voodoo Lady voices her true nature and allegiance to Guybrush

The Voodoo Lady is a recurring side-character who often gives advice to Guybrush Threepwood, known as a nameless voodoo priestess, who keeps a careful watch over the seas for those who would misuse the powers of voodoo for sinister purposes, specifically the demon pirate, LeChuck, and his sinister cohorts. Her importance in the first game is somewhat fleeting as the game can be completed without talking to her, but in all her subsequent appearances she plays a key role to the player's progress. While she aids Guybrush numerous times throughout the series, her true allegiance and nature becomes much more clouded and sinister as the series progresses, eventually revealing the Voodoo Lady as a keen manipulator who exploits and even indirectly causes many of the events over the course of the series through her ambiguous guidance for her own agenda.

The exact contents of such an agenda are unclear, though she urges Guybrush to believe that she has always had his best interests at heart and seemed to genuinely value his heroism in taking down LeChuck, a man who she claims was always doomed to have a villainous life and destiny. While it is known that she has helped both Guybrush and LeChuck in various ways, it is made clear that she sees LeChuck as a true abomination who exploits the powers of voodoo for destruction and his own insidious purposes without following the natural state of order and must be taken down for the good of the Caribbean and beyond. Guiding the fates of Guybrush, Elaine Marley, and LeChuck, the Voodoo Lady is keen to ensure that certain events throughout the Seven Seas follow a specific path for an unknown goal. Her clouded nature, past, and agenda have served as one of the series' most pivotal and elaborate plot points throughout the games with varying levels of importance towards each game's plot.

Meathook is a fairly well-known if not prominent supporting character in the Monkey Island series, serving as a pirate on Guybrush's crew and an artist.

Otis is a supporting character who appears in the first and fourth games. He is imprisoned multiple times for picking flowers illegally, although he protests his innocence, claiming that it is merely a plot to make him seem less threatening and bloodthirsty. He twice agrees to be on Guybrush Threepwood's crew.

Otis's appearance changes very little between the two games: he wears a white blouse, knee-long pants and black shoes in both of his appearances. However, in the first game he also donned a noticeable purple bandanna. In MI4 his hair colour is changed from black to carrot-orange for unspecified reasons. Also, while in the first game he appeared to speak perfect English he has a noticeable, puzzlingly Mexican-sounding accent in the fourth game.

Carla the Swordmaster is, as her name suggests, the famous Swordmaster of Mêlée Island. The Sword Master's House is deep in the forest of Mêlée.

Murray is a disembodied talking skull. He was separated from his body when Guybrush Threepwood shot his rowboat out of the water during the battle for Plunder Island at the beginning of The Curse of Monkey Island. In their first conversation together Murray's disposition and megalomania become apparent since despite having no arms or body he intends to rule the world.

Murray has become a fan favourite, resulting in cameo appearances in the fourth and fifth games. He was featured in the initial test-versions of CMI and became so popular that he was given more appearances throughout the game. Murray's unrelenting megalomania while at the same time being completely unable to do anything other than talk and hop around is thought to make him a popular character.

"Remember, wherever you go, on sea or on land, you can't ever hide from Largo Lagrande!"

Largo LaGrande is a short but physically mighty henchman of LeChuck's and is often credited as being his former right-hand man, having aided the notorious pirate in his nefarious deeds throughout his reign of terror as a human and ghost, specifically by locating the pirate's corpse and burying it securely within LeChuck's Fortress. Since LeChuck's demise at the hands of Guybrush Threepwood, Largo managed to evade capture and was charged with the task of locating a piece of LeChuck's spiritual essence by his Voodoo Priest to resurrect their old master's corpse as a zombie pirate. While attempting to accomplish this mission, however, Largo began to indulge in his own ambitions of being a feared and powerful pirate himself and used his reputation as a follower of LeChuck to seize control over Scabb Island and obtain all the wealth and pleasures he lusted to have for himself, usually at the expense of others.

When Guybrush arrives on the island to start his quest to find the mystical treasure of Big Whoop, Largo and him immediately take a strong dislike to each other with Guybrush eventually torturing Largo off the island with the use of a voodoo doll. However, Largo is able to steal the ghost beard of LeChuck that Guybrush had kept on his person as a memento and uses it to resurrect LeChuck once again. Largo then spends the majority of his appearances serving LeChuck and aiding him in building up his forces once again and capturing Guybrush, all the while being increasingly threatened by LeChuck if he fails in his tasks.