Studies pertaining to muscle dysmorphia (MD) have concentrated the most on males. However, a new body ideal for women is emerging: a very toned, athletic body with flat, smooth muscles. The emphasis on the level of muscularity represents a contribution to the growth of MD symptoms in women. The aim of this study was to evaluate the factorial structure and psychometric properties of the muscle dysmorphic disorder inventory (MDDI) in two samples of physically active Italian women. One-hundred and sixty-five women practicing non-competing bodybuilding/powerlifting and 353 women practicing physical exercise completed the MDDI and measures of features associated with MD. Findings of the confirmatory factor analysis showed a three-factor structure with acceptable fit and invariant across groups. Omega coefficients revealed adequate internal consistency for all the scales and for the total score of the MDDI. Furthermore, convergent and divergent validity as well as retest reliability emerged to be good. MDDI represents a reliable measure of MD symptoms in physically active Italian women.