Objective: To explore the effect of social support and rumination on posttraumatic growth of patients with human immunodeficiency virus (HIV). Methods: A total of 1 152 patients with HIV from Shanghai Public Clinical Center were investigated using General questionnaire, Perceived Social Support Scale, Event Related Rumination Inventory and Posttraumatic Growth Inventory by cross-sectional survey method from January 2018 to October 2018. The path of social support and rumination on post-traumatic growth was established by correlation analysis and structural equation model. Results: The total score of posttraumatic growth in patients with HIV was (47.93±23.55) points, which was at the low-middle level. Correlation analysis showed that posttraumatic growth was positively correlated with comprehension of social support (r=0.234, P<0.01), positively correlated with rumination (r=0.352, P<0.01). Structural equation model showed social support had directly positive effect on posttraumatic growth, path coefficient were 0.55. Rumination had a partial mediating effect between social support and posttraumatic growth, and mediation effects account for 11.65% of the total effect. Conclusions The posttraumatic growth level of patients with HIV needs to be improved. Health care providers should help patients get as high a level of social support as possible, as well as focus on guiding patients to think positive about the disease.