OBJECTIVE To explore the difference between adolescent and adult C57BL/6J mice in response to rapid eye movement sleep (REMS) deprivation in terms of anxiety behavior and hippocampal NO level. METHODS Both adolescent and adult C57BL/6J mice were divided into normal control (NC) group, wide platform (WP) group, and 24-hour REMS deprivation group, each group consisting of 15 mice. REMS deprivation models were established using a small platform in water tank, and the elevated plus maze test was used to examine anxiety behavior of the mice. After behavioral tests, the mice were sacrificed to examine hippocampal NO levels using enzyme-linked immunosorbent assay, and hippocampal nNOS protein expression was detected with Western blotting. RESULTS The adolescent C57BL/6J mice showed no obvious differences in anxiety behaviors between the 3 groups, but NO level and nNOS expression in the hippocampus was significantly higher in REMSD group than in NC and WP groups (P<0.01). The adult mice in REMSD group, compared with those in the other two groups, exhibited significantly increased total number of arm entry (P<0.01), lowered number of open arm entry and reduced open arm time (P<0.01), increased number of close arm entry and prolonged close arm time (P<0.01 or 0.05); no obvious differences in NO level or nNOS expression in the hippocampus were found in the 3 groups of adult mice. CONCLUSION REMS deprivation produces different effects on anxiety-related behaviors between adolescent and adult mice possibly in relation to their different responses in terms of NO levels and nNOS expression in the hippocampus.