To investigate the correlation between antidepressant effects of paeoniflorin and albiflorin on mice and NO/cGMP signal transduction pathway. Methods:Radix Paeoniae Rubra and Radix Paeoniae Alba was intragastric administered to the mice to establish the mice model of antidepressant with tail suspension test (TST), and the time of immobility was recorded. The same methods were used to study paeoniflorin and albiflorin. And the NO/cGMP pathway related indicators of cerebral cortex and hippocampus were detected. Results:Compared with model group, 2 g/kg Radix Paeoniae Rubra and 2 g/kg, 1 g/kg Radix Paeoniae Alba can reduce the immobility time of tail suspension (P<0.05, P<0.001, P<0.05). Compared with the same dose of Radix Paeoniae Rubra, the TST immobility time of 2 g/kg Radix Paeoniae Alba were obviously lower (P<0.05). Compared with model group, 20 mg/kg paeoniflorin, 20 mg/kg albiflorin can reduce the immobility time of tail suspension and the content of NO, cGMP (P<0.05, P<0.001); Compared with the same dose of paeoniflorin, the immobility time of tail suspension and the content of NO of 10 mg/kg albiflorin were obviously lower (P<0.05). Compared with model group, 20 mg/kg paeoniflorin and 20 mg/kg albiflorin can reduce the mRNA expression of nNOS, GluR1 (P<0.05, P<0.01, P<0.05). Conclusion:Radix Paeoniae Alba has antidepressant effect, and paeoniflorin and albiflorin are the material basis of the antidepressant effect of Radix Paeoniae Alba; however, in the administration range of this experiment, the antidepressant effect of Radix Paeoniae Rubra is not obvious compared with that of Radix Paeoniae Alba, which may be related with it mainly containing paeoniflorin which antidepressant effect is weaker, but not containing albiflorin which antidepressant effect is stronger.