The three wise monkeys are a pictorial maxim, embodying the proverbial principle "see no evil, hear no evil, speak no evil". The three monkeys are Mizaru, covering his eyes, who sees no evil; Kikazaru, covering his ears, who hears no evil; and Iwazaru, covering his mouth, who speaks no evil. Lafcadio Hearn refers to them as the three mystic apes in his Glimpses of unfamiliar Japan.

There are various meanings ascribed to the monkeys and the proverb including associations with being of good mind, speech and action. In the Western world the phrase is often used to refer to those who deal with impropriety by turning a blind eye.

Outside Japan the monkeys' names are sometimes given as Mizaru, Mikazaru, and Mazaru, as the last two names were corrupted from the Japanese originals. The monkeys are Japanese macaques, a common species in Japan.