<p>Negative weight-conversations between parents and their children are often harmful to youth health and psychosocial outcomes. However, most research to date does not distinguish between positive and negative comments. The current research aimed to develop scales for a measure that captures different types of weight-conversations, identify a factor structure for a psychometrically sound model, and validate the measure. We recruited a national sample of adolescents and their parents (<i>N</i> = 503). Items were developed based on extant literature, cognitive interviews, and expert review. First, the items were tested through exploratory factor analysis (EFA) on one half of the sample, and then confirmatory factor analysis (CFA) on the other half. Exploratory and confirmatory factor analyses identified a three-factor model: Weight-Focused, Health-Focused Conversations, and Body Positivity Conversations. The model demonstrated strong (scalar) invariance across demographics, with no items exhibiting differential item functioning. Validity was examined via correlations. Criterion validity showed that all three Weight-Conversation subscales were positively correlated with dieting and unhealthy weight control behaviors. Convergent validity was supported for the Body Positivity subscale with body satisfaction, while discriminant validity was found for the Weight-Focused and Body Positivity subscales with social desirability. Sensitivity analyses revealed varying results for discriminant validity across different racial/ethnic groups. The current research resulted in a psychometrically tested measure to assess parent-adolescent weight-conversations, offering a valuable tool for future research on adolescent health and psychosocial outcomes across diverse populations. However, qualitative analysis is needed in racial/ethnic groups to understand potential differences in weight conversations.</p>