To identify factors associated with health-related quality of life among overweight or obese adults. The obesity epidemic presents a global challenge. Obesity is associated with lower health-related quality of life; however, no study has comprehensively examined correlates of health-related quality of life in this population. A cross-sectional design. The physical component score, mental component score and eight domain scores of the Short Form-36 v2 were used to assess health-related quality of life. We identified 23 possible correlates of health-related quality of life, including age, body mass index, health and weight histories, perceived stress, cholesterol-lowering diet self-efficacy, problem-solving, binge eating, dietary intake and physical activity. Correlational analyses were used to examine the bivariate associations between correlates and health-related quality of life variables. All possible subsets regression was used to develop predictive models of health-related quality of life. The sample (n = 210) was predominantly White (84·8%), female (78·1%) and middle-aged (average age = 46·80 years). Age, body mass index, education, having children at home, and being hypertensive were identified as the best predictors of physical component score, explaining about 9% of the variance. Age, marital status, having hyperlipidaemia, perceived stress, problem-solving, self-efficacy, binge eating and barriers to healthy eating predicted mental component score, explaining approximately 48% of the variance. Physical functioning and role physical domains of health-related quality of life had similar sets of predictors, with 15% and 13% of the variance explained, respectively, while similar predictors were identified for bodily pain (6%), general health (26%), vitality (40%), social functioning (32%), role emotional (42%) and mental health (46%) domains. Psychosocial factors were associated with the mental-related quality of life. Further exploration of factors related to physical-related quality of life is warranted in this population. When working with overweight/obese adults who are trying to lose weight, nurses need to consider socio-demographic and psychosocial factors in the development of a treatment plan that will improve health-related quality of life in this population.