Abstract： Objective： To observe the clinical effect of Shugan Jieyu tang for senile patients with depression of liver qi depression type，and explore its mechanism and safety. Methods：A total of 70 cases of senile patients with depression of liver qi depression type were selected and divided into the control group and the observation group according to the random number table method， 35 cases in each group. The control group was treated with venlafaxine hydrochloride sustainedrelease capsules，and the observation group was additionally treated with Shugan Jieyu tang based on the treatment of the control group. The scores of 17- item Hamilton Depression Scale(HAMD- 17) and Chinese medicine syndromes in the two groups were compared before and after treatment；the levels of cortisol(CORT)，noradrenaline(NA)，5- hydroxytryptamine (5-HT) and brain-derived neurotrophic factor(BDNF) in serum were detected；adverse reactions were observed；the clinical effect was evaluated. Results： The total effective rate was 80.00% in the control group and 94.29% in the observation group， there being no significance in the difference(P＞0.05). Before treatment， there was no significant difference being found in the comparison of the scores of HAMD- 17 and Chinese medicine syndromes between the two groups(P＞0.05). After treatment， the scores of HAMD- 17 and Chinese medicine syndromes in the two groups were decreased when compared with those before treatment(P＜0.05)，and the above scores in the observation group were lower than those in the control group(P＜0.05). Before treatment，there was no significant difference being found in the comparison of the levels of CORT，NA，5-HT and BDNF in serum between the two groups(P＞0.05). After treatment，the levels of CORT in serum in the two groups were lower than those before treatment，and the levels of NA，5-HT and BDNF in serum were higher (P＜0.05)；the level of CORT in serum in the observation group was lower than that in the control group，and the levels of NA，5- HT and BDNF in serum were higher(P＜0.05). There was no significant difference being found in the comparison of the incidences of adverse reactions between the two groups(P＞0.05). Conclusion：The application of Shugan Jieyu tang for senile patients with depression of liver qi depression type can improve their depression with few adverse reactions. The mechanism may be related to the regulation of the expressions of CORT，NA，5-HT and BDNF.