OBJECTIVE: To examine associations of stress and sleep with diet quality of family child care home (FCCH) providers, and whether self-efficacy for healthy eating influences these associations. DESIGN: A cross-sectional analysis was performed using baseline data (2013-2015) from a randomized control trial with FCCH providers. PARTICIPANTS: The study included 166 licensed FCCH providers, aged >18 years, from central North Carolina. MAIN OUTCOME MEASURE(S): Diet quality was assessed with a food frequency questionnaire, used to calculate a modified 2010-Healthy Eating Index score. Stress, sleep quality, and diet self-efficacy were measured via self-administered questionnaires. ANALYSIS: Using observations from 158 participants with complete data, multiple linear regression models were created to assess whether stress, sleep quality, and diet self-efficacy were associated with diet quality and whether diet self-efficacy moderated these associations (significance set at P < 0.05). RESULTS: In the initial model, only diet self-efficacy was significantly associated with diet quality (β = 0.32; P < 0.001). Moderation analyses showed that higher stress was associated with lower diet quality, but only when diet self-efficacy was low. CONCLUSIONS: Building FCCH providers' self-efficacy for healthy eating is an important component of health promotion and can buffer the impact of stress on their diet quality.