This paper examines the relationship between Human Resource Development (HRD) practices and managerial efficiency in India’s oil and gas sector. Using a comparative approach, the study analyzes data from four major Oil Public Sector Undertakings (PSUs) to determine how key HRD functions-including manpower planning, recruitment and selection, career planning and growth, employee engagement, and training and development-affect overall managerial performance. A mixed-methods design was employed, involving both quantitative data gathered through structured questionnaires and qualitative insights from secondary sources. Statistical analyses such as Pearson correlations, ANOVA, and Data Envelopment Analysis (DEA) were conducted to test the relationships between HRD practices and managerial efficiency. The findings indicate that effective HRD practices significantly enhance managerial performance. In particular, employee engagement and career planning demonstrated the strongest associations with managerial efficiency, while digital integration in recruitment and training emerged as a critical enabler of operational excellence. The study contributes to the theoretical literature by extending the Harvard Framework and Michigan Model, and it provides practical recommendations for policy makers and organizational leaders to improve HR strategies. Future research should consider a longitudinal design and comparative studies with private sector enterprises to further validate these findings.