INTRODUCTION Few studies have investigated the factors that affect the relationship between body image dissatisfaction and disordered eating locally. Our study aimed to investigate the moderating effects of depression and anxiety levels on the body dissatisfaction-disordered eating link in Singapore. METHODS A total of 329 participants completed a set of questionnaires that included various scales pertaining to eating behaviours, body image, psychological distress and quality of life. RESULTS Participants were diagnosed with schizophrenia (47.4%), depression (46.8%) and substance use disorders (5.8%). Moderation analyses revealed that depression (F [9, 251] = 18.50, p < 0.001, R2 change = 0.021) and anxiety levels (F [9, 268] = 19.54, p < 0.001, R2 change = 0.014) were significant moderators of the relationship between body dissatisfaction and disordered eating scores. Subsequent multivariate linear logistic regression analyses showed that high disordered eating scores were significantly associated with lower physical (F [8, 273] = 9.59, R2 = 0.22, p < 0.001, β = −0.27, p < 0.001), psychological (F [8, 273] = 10.51, R2 = 0.49, p < 0.001, β = −0.27, p < 0.001), social (F [8, 256] = 6.78, R2 = 0.18, p < 0.001, β = −0.18, p = 0.004) and environment (F [8, 273] = 5.29, R2 = 0.13, p < 0.001, β = −0.19, p = 0.001) quality of life scores after controlling for sociodemographic covariates. CONCLUSION Greater effort should be dedicated to the screening of disordered eating behaviours in psychiatric outpatients presenting with greater psychological distress.