Objective The prevalence rate, related factors and clinical characteristics of postpartum depression were studied in order to promote obstetrician′s understanding of the disease, and resort to preventive and therapeutic measure earlier. Methods Two hundred and ten puerpera were selected from September to November 1998 for mood study by self rating depression scale, self rating anxiety scale, Hamilton depression scale, and self made questionnaires. Results The prevalence rate of postpartum depression was 37 14% (78/210), of which, 91 03% (71/78) was mild, and 8 97% (7/78) moderate. In addition, 10 48% (22/210) of women got anxiety after delivery. The symptoms, including decreased activity, difficulty in thinking, problems in decision making, difficulty in doing things, feeling of uselessness and hopelessness were chief complaints of postpartum depression patients. Bad social behavior and mood controlling, inadequate psychological preparation for delivery, lack of knowledge of delivery were closely correlated to the onset of postpartum depression, which are the risk factors of postpartum depression. Conclusions Postpartum depression is a spiritual and psychological obstacle with relatively high prevalence rate. Bad social psychological factors can bring out and aggravate postpartum depression. It is important to carry out prenatal psychological care and to propagate the knowledge of delivery, to find out and cure of postpartum depression as soon as possible.