Objective: Although health and wellness behaviors are associated with positive body image, research is limited regarding the relationship between sleep and positive body image. We propose that negative affective states may link sleep and body image. Specifically, we examined whether better sleep may relate to positive body image through reductions in negative affective experiences. Participants: Participants were 269 undergraduate women. Methods: Cross-sectional surveys were administered. Results: We found correlations in the expected directions between sleep, positive body image variables (i.e., body appreciation, appearance evaluation, and appearance orientation), and negative affective states (i.e., depression, anxiety, and stress). There were group differences in negative affective states and body image based on adequate sleep. Data supported indirect effects of sleep through depression on appearance evaluation, and through depression and stress on body appreciation, respectively. Conclusions: Our findings indicate sleep warrants further research attention as a wellness behavior related to more positive body image.