This work proposes that trait body dissatisfaction rests on two dissociable components: 1) frequency of body dissatisfaction episodes, and 2) duration of such episodes, with higher trait body dissatisfaction resulting from more frequent and/or prolonged episodes. The current research aimed to develop a measure of these two dimensions (i.e., the Body Dissatisfaction Frequency Duration Questionnaire; BDFDQ) and test this theoretical model by investigating whether body dissatisfaction frequency and duration 1) were structurally dissociable, 2) meaningfully dissociable, and 3) each associated with different aspects of disordered eating behavior. Study 1 (N = 300, 42% women) developed the BDFDQ and showed that frequency and duration are structurally dissociable. Study 2 (N = 400, 50% women) showed that the two-factor model was invariant across gender and both subscales showed good psychometric properties of reliability and validity. Results further supported that frequency and duration are meaningfully dissociable by revealing that each component accounted for unique variance in trait body dissatisfaction. Study 3 (N = 279, 77% women) replicated Study 2 findings and established that frequency and duration subscales each associated with different aspects of disordered eating behavior. Together, findings imply that body dissatisfaction frequency and duration represent two separable dimensions underlying trait body dissatisfaction.