Objective To evaluate the effects of baijin capsule on behavioral changes and monoamine neurotransmitters concentration in chronic unpredictable mild stress ( CUMS ) depression rat model.Methods The depression rat model was induced by11-week chronic unpredictable mild stress combining with solitary.After the model were established, rats were given the decoction of baijin capsule ( 12.6 g/kg, 4.2 g/kg, 1.4 g/kg ) or fluoxetine hydrochloride (3.5 mg/kg) by intragastricfor 4 weeks.During the experiment period, sucrose consumption and open-field experiment were conducted to monitor the behavior of rats, such as sucrose consumption percentage, horizontal motion, and vertical motion.At the end of the experiment, the levels of the monoamine neurotransmitters in the cerebral cortex and hippocampus were analyzed by method of high performance liquid chromatography-electrochemistry.Results Compared with the normal group, the weight, horizontal displacement distance, vertical movement times, and sucrose consumption percentage of rats in model group decreased significantly after stimulated with CUMS and solitary for 7 weeks (P<0.05,P<0.01).Compared with model group, consecutively administrated for 4 weeks, horizontal displacement distance, vertical movement times, and the percentage in sugar water consumption significantly increased with the treatment of baijin capsule (P<0.05, P<0.01).Meanwhile, the content of norepinephrine (NE), dopamine (DA), and 5-hydroxytryptamine (5-HT) in the cortex were significantly increased in rats of the baijin capsule ( P <0.05 ) .Conclusions The results indicated that baijin capsule improved the behavioral disturbances in depression rat model, which were related to enhancement of the concentration of monoamine neurotransmitters in the cortex.