The purposes of this cross-sectional study were two-fold. The primary aim of this study was to test whether the Muscle Appearance Satisfaction Scale (MASS), a recently developed, reliable, and valid measure of muscle dysmorphia symptoms, measures a parallel phenomenon in men that the Body Shape Questionnaire (BSQ) does in women, i.e., overconcern with body size and shape. To test this aim, psychosocial correlates for overconcern with body size and shape in women were tested to be the same psychosocial correlates for a measure of muscle dysmorphia in men. The psychosocial variables included in this model were body dissatisfaction, negative affect, internalization of the thin and muscular cultural ideals, low self-esteem, history of weight-related teasing, and BMI. The sample consisted of 204 volunteers, with men (n = 80) and women (n = 124) represented. All participants were 18 years of age or older (mean age = 21.34, SD = 3.34). The results indicated that women scored higher on the BSQ than men, and conversely men scored higher on the MASS in comparison to women. Additionally, the pattern of correlations differed between MASS scores and the psychosocial variables for men, and the pattern of correlations between BSQ scores for women with the same psychosocial variables. Of the variables tested, only internalization of cultural body ideals and body size dissatisfaction were significantly correlated with menís scores on the MASS. Negative affect was also significantly correlated with men's MASS scores, but depression symptom severity was not. Evidence from this study did not support the hypothesis that the MASS measures the same construct in men that the BSQ measures in women, i.e., an overconcern with body size and shape. Therefore, continued research to identify or develop a measure of concern for body size and shape that is valid for men is needed, in order to effectively compare men and women on this construct.