Objective To identify the high risk factors related to postpartum suicide. Methods A total of 40 women with postpartum depression who had suicidal act or ideation were included in the study. They were evaluated by the Edinburgh Postpartum Depression Scale (EPDS), the Life Events Scale (LES) and the Social Support Rate Scale (SSRS), and compared with healthy postpartum women. The multi-element gradual regression analysis was performed to identify the high risk factors. Results Such factors as prior history of depression, negative life events within the previous half year, absence of social support, disease of mothers or infants, and conjugal relationship were significantly correlated with postpartum suicide. Conclusion It might be helpful to reduce the incidence of postpartum suicide by prenatal mental intervention and postpartum crisis intervention.