The aim of this study was to develop a scale assessing high school students' self-efficacy beliefs in chemistry-related tasks and to assess psychometric properties of scores on this scale. A pilot study with a sample of 150 high school students provided initial evidence for two-factor structure of 16-item scale, named High School Chemistry Self-Efficacy Scale (HCSS). The final form of the HCSS was administered to 362 high school students in Turkey. Confirmatory factor analysis fit indices and factor pattern coefficients supported the proposed structure, with the two factors directly corresponding to the hypothesized dimensions. These dimensions were chemistry self-efficacy for cognitive skills ( 10 items, alpha reliability = .90) and self-efficacy for chemistry laboratory (6 items, alpha reliability = .92). In addition, the two-factor model for the HCSS was invariant across school types. Analyses of latent mean structure indicated that private school students were statistically more efficacious than public school students in chemistry laboratory skills. The HCSS is a promising tool to identify chemistry self-efficacy beliefs in high school students.