This study described the process of developing and validating the College Chemistry Self-Efficacy Scale (CCSS) that can be used to assess college students' beliefs in their ability to perform essential tasks in chemistry. In the first phase, data collected from 363 college students provided evidence for the validity and reliability of the new scale. Three dimensions emerged: self-efficacy for cognitive skills, self-efficacy for psychomotor skills, and self-efficacy for everyday applications. In the second phase, data collected from an independent sample of 353 college students confirmed the factorial structure of the 21-item CCSS. The Cronbach alpha coefficients ranged from 0.82 to 0.92. In addition, each dimension of the CCSS had moderate and significant correlations with student chemistry achievement and differentiated between major and non-major students. Followed by the additional validation studies, the CCSS will serve as a valuable tool for both instructors and researchers in science education to assess college students' chemistry self-efficacy beliefs.