Objective: The factor structure of the Grit-S is the subject of much debate. The purpose of this study was to examine the factor structure of the Grit-S and validate its psychometric properties among racially/ethically minoritized adolescents using Item Response Theory (IRT). Method: Data were collected from 651 racially/ethnically minoritized adolescents who were enrolled in a college access program in a U.S. northeastern state. Results: The analysis indicated the Grit-S has a correlated two-factor model, consisting of a Perseverance of Effort (PE) subscale and a Consistency of Interest (CI) subscale, without a higher-order grit factor. Moreover, item information curves indicated the PE subscale has a low precision at the higher level of theta. The concurrent validity with self-efficacy indicated PE has a strong correlation with self-efficacy while CI does not. Conclusions: The Grit-S may need to be revised to assess the concept of grit for racially/ethnically minoritized adolescents. Valid measurement of the grit construct is crucial to applied research and evaluation of interventions specifically designed to promote grit in adolescents. Additional research is needed to examine how racially/ethnically minoritized adolescents understand the concept of grit.