Antibody to the hepatitis A virus HAV (anti-HAV IgG) were detected by ELISA in sera from 183 monkeys captive reared under different condition , and the total positive rate was 68.9%. Antibody positive rate in individual cage reared monkeys was significantly lower than that in colony reared ones (P<0.05), increasing with age. Antibody to HAV in 41 wild-caught monkeys were detected and the positive rate was 19.5%, which was significantly lower than that in captive-rearing ones (P<0.05). The results obtained from this investigation had great importance in monkeys rearing management