Using social cognitive theory as a theoretical framework, the current study examined the mediating role of mastery experience between other sources (vicarious experience, social persuasion, and physiological state) and chemistry self-efficacy for cognitive skills, which can be defined as students' beliefs in their capabilities to successfully perform intellectual operations in chemistry. Data were collected from 397 high school students through the High School Chemistry Self-Efficacy Scale and Sources of Self-Efficacy Scale. Results of structural equation modeling indicated that mastery experience and vicarious experience directly influenced chemistry self-efficacy. In addition, a mediation effect of mastery experience was found for social persuasion and physiological state, while no mediation was found for vicarious experience. Overall, 50% of variance in chemistry self-efficacy for cognitive skills is explained by, or predicted from, the direct and indirect influences of mastery experience.