Gynecomastia is the proliferation of breast tissue in men. The purpose of this study was to compare psychological functioning across three groups of participants: treatment seeking men with gynecomastia, non treatment seeking men with gynecomastia, and men without gynecomastia. Though very little research has been done with this population, some research suggests poor psychological outcomes of gynecomastia. MANCOVA was used to test differences in psychological functioning across the three groups, and multiple regression was used to predict quality of life from psychological variables. Significant differences emerged between groups, with men with gynecomastia reporting worse psychological functioning. Additionally, no theoretical model for body image currently exists for men with gynecomastia. As such, the Tripartite Influence Model of Body Image was examined in this population through used of mediation analyses. Results confirmed partial support of this model for this population. This study was the first to examine treatment seeking status as a potential moderator of psychological functioning in men with gynecomastia and provides a theoretical model of body image to guide future research in this area.