The current study utilized a sample of 183 patients, in romantic relationships, who were either pre‐ or post‐weight loss surgery (WLS), to assess (a) associations between romantic relationship factors and pre‐ and post‐surgery body mass index (BMI), (b) the positive and negative influences of obesity in romantic relationships, and (c) the influence of romantic relationship factors on BMI and the reciprocal. Correlations, confirmatory factor analysis, and multiple linear regression were conducted. Patients endorsed greater negative influence of obesity in their romantic relationships compared to positive influences, and their romantic relationship quality was predicted by several variables, including BMI, in pre‐ and post‐surgery patient groups.