Bariatric surgery has been recognized as the gold standard treatment for severe obesity. Although postbariatric surgery patients usually achieve and maintain substantial weight loss, a group of individuals may exhibit weight regain. Several factors are proposed to weight regain, including psychiatric comorbidity. The objective of the study is to conduct a systematic review and meta‐analysis of studies investigating the relationship between psychiatric comorbidity and weight regain. A systematic review through PubMed, Web of Science, Cochrane Library, Scopus, and PsycINFO was performed, following Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA). After a stepwise selection, 13 articles were included in the qualitative analysis and 5 were included for a meta‐analysis. Women was majority in most of the studies (87.6%), and a bypass procedure was the bariatric intervention most evaluated (66.8%), followed by gastric banding (32.1%) and sleeve (1.1%). Higher rates of postbariatric surgery eating psychopathology were reported in patients with weight regain. However, the association between general psychopathology and weight regain was not consistent across the studies. In the meta‐analysis, the odds of eating psychopathology in the weight regain group was higher compared with the nonweight regain group (OR = 2.2, 95% CI 1.54‐3.15). Postbariatric surgery eating psychopathology seems to play an important role in weight regain.