PURPOSE: This study was to develop a Health Dieting Competency (HDC) scale to assess self-rated health dieting competence of college students. METHODS: The scale was developed as follows: items generated, and tests of validity and reliability. Items were developed through a literature review, review of instruments, and interviews. A panel of four experts reviewed the scale for content validity. Factor analysis, Pearson correlation, descriptive statistics and Cronbach's alpha were used to analyze the data (N=183). RESULTS: In the preliminary stage, thirty-three items were generated. Final items were fourteen that were selected through exploratory factor analysis. The HDC scale was consisted with five factors and fourteen items that were Goal-Directed (5-items), Health Support (2-items), Health Self-Efficacy (3-items), Health Perception (2-items), and Escaping from Health (2-items). The internal consistency of HDC as measured by Cronbach's alpha was .78. CONCLUSION: Content validity, construct validity, and reliability of the HDC were established. The HDC scale is a reliable and valid instrument for early adulthood youth who are willing to assess health dieting competency.