The purpose of this study is to develop the American Meritocracy Myth Stress Scale (AMMSS), capable of assessing college students’ psychological stress within the context of the pervasive myth of meritocracy. This psychological stress stems from the association between their perceptions of their own hard work and social class mobility. Underpinned by the social class worldview model-revised, American meritocracy myth stress is conceptualized as the psychological stress that individuals experience when disequilibrium exists between the dominant and pervasive meritocracy ideology and their efforts to climb the social ladder through hard work. Three substudies were conducted for exploratory factor analysis (Study 1: n = 887); confirmatory factor analysis, validity, and measurement invariance (Study 2: n = 903); and 2-week test–retest reliability (Study 3: n = 37). The results of these studies provide empirical support for the AMMSS. We discuss implications for practice, advocacy, training, and future research.