Náin II (TA 2338 - TA 2585) was a dwarf of Durin's Folk and a King of Durin's Folk.
Náin was born in the Grey Mountains (Ered Mithrin), and the son of Óin. He succeeded his father in TA 2488. Under Náin II, the dwarves lived peacefully in the mountains but the time of the Watchful Peace had come to an end and many dangers were growing from the West and North. During the final years of his reign, the dragons came down from the northern wastes and began to make war upon the dwarves.
Náin was 247 years old when he died. He was succeeded by his son, Dáin I. He had a younger son Borin, from whom several of Thorin Oakenshield's companions were descended.