This study aimed to develop and validate a career competency scale tailored for behavior analysts to support sustainable career development and enhance professional expertise. Key dimensions of career competencies were identified through a comprehensive literature review, and the scale was constructed and rigorously validated using expert input, exploratory factor analysis, and confirmatory factor analysis. The finalized scale comprises 11 items encompassing four dimensions: Reflection, Career Management, Job Exploration, and Self-Information Collection. The confirmatory factor analysis demonstrated robust psychometric properties, with fit indices meeting established thresholds, thereby affirming the scale’s reliability and validity. This study provides a theoretically grounded and empirically validated tool that addresses the unique occupational characteristics and contextual demands of behavior analysts. The scale holds significant practical implications for self-assessment, professional training design, and evidence-based workforce evaluation. Future research should investigate the linkage between career competencies and service quality outcomes, thereby broadening the scale’s applicability and contributing to the advancement of behavioral rehabilitation practices.