Background: Cambodian youth face many unique challenges, such as high instances of poverty and intergenerational trauma. Grit, a person-level trait defined as having "perseverance and passion for long-term goals", may be particularly important in helping Cambodian youth to succeed despite the extreme challenges they face. To date, the Original Grit Scale (Grit-O) has not been translated in Khmer or validated for a sample of Cambodian youth. Purpose: This study aimed to assess the reliability and validity of a Khmer translation of the Original Grit Scale (Grit-O) among urban Cambodian youth. Research Design: A cross-section survey battery--including Grit-O and other relevant covariates--was administered to Cambodian youth. Study Sample: Data were collected from 580 Cambodian adolescents (M[subscript age] = 15.85 years, SD[subscript age] = 2.05, 63.7% female). Data Collection and Analysis: Paper and pencil surveys were sent home from school with each participant and returned to the study team the next day. Analyses included calculating Cronbach's alphas, interitem correlations, correlations with relevant covariates and both a confirmatory and exploratory factor analysis. Results: Cronbach's alphas and interitem correlations indicated that the full scale was not reliable for this sample, and that reliability improved when two items ("I become interested in new pursuits every few months--reverse-scored and I finish whatever I begin") were excluded. The subscales "Consistency of Interests and Perseverance of Effort" were more reliable than the full scale. Correlations with relevant covariates indicated that the full scale was moderately valid. Factor analyses suggested that items 6 and 7 did not load well onto either identified factor. Conclusions: Investigators measuring grit in a sample of Cambodian youth should consider excluding items 6 and 7 of Grit-O, and assessing the two subscales on their own, rather than treating them as indicators of a single higher-order construct.