A restraint device for primates capable of providing accurate visual psychological results of experiment by reducing stress given to the primates as subjects and stabilizing the psychological state of the primates. A box-like body (12) formed of a transparent material comprises foot stands (70), a waist stand (72), a first restraint (40) for restraining a body, and a second restraint (42) for restraining a neck in this order starting at the lower part. In both restraints, the first cutout parts (40aa, 42aa) of first plate-like bodies (40a, 42a) and the second cutout parts (40bb, 42bb) of second plate-like bodies (40b, 42b) are mutually overlapped with each other in the directions reverse to each other to form a first hole (50) for restraining the body and a second hole (52) for restraining the neck while adjusting their sizes. The heights and the inclinations of the first and second restraints can be adjusted.