Japanese macaques reproduce sexually, with the female carrying a single offspring for about six months and providing long-term care. The gestation period is five months and three weeks, and a litter consists of one to two young. The species develops on land, outside of bodies of water, and young develop in nests built on or near the ground. These nests are located directly on the surface of the ground. Only the mother displays parental care for the offspring. Live young are born on land, not hatched from eggs or larvae. Sexual maturity occurs between three years and six months and seven years. The interval between reproduction is one to two years. Mating frequently occurs during colder periods.