Objectives: To examine the effects of cognitive–behavioral therapy weight loss (CBTWL) interventions on weight loss, psychological outcomes (eating behaviors [cognitive restraint, emotional/binge eating], and depressive/anxiety symptoms) in adults with overweight or obesity. Methods: To be included, studies had to (a) be randomized controlled clinical trials of a CBTWL intervention versus a comparison intervention; (b) include weight loss and psychological outcomes; and (c) include patients who were at least overweight to obese. This review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (Moher, Liberati, Tetzlaff, & Altman & the PRISMA Group, 2009). Results: Twelve studies (6,805 participants) were included. The average weight loss difference between arms was −1.70 kg (95% confidence interval [CI]: −2.52 to −0.86, I2 = 1%) in favor of CBTWL. The standardized mean difference on cognitive restraint was 0.72 (95% CI: 0.33 to 1.09; I2 = 81%) and −0.32 (95% CI: −0.49 to −0.16; I2 = 0%) for emotional eating in favor of CBTWL. The reduction in depressive symptoms was not statistically different between the groups (−0.10 [95% CI: 0.21 to 0.02], I2 = 36%). Meta-analyses were not possible for anxiety and binge eating. Conclusions: In addition to weight loss, current evidence suggests that CBTWL is an efficacious therapy for increasing cognitive restraint and reducing emotional eating. However, CBTWL does not seem to be superior to other interventions for decreasing depressive symptoms. Future studies should focus on understanding how psychological factors impact weight loss and management.