The Excellence Initiatives represent a significant investment in higher education, yet little is known about the causal impact of these programs on doctoral students and future researchers. Using a comprehensive student-level dataset, we apply a difference-in-differences approach to identify how China’s Double World-Class (DWC) Project affects PhD students’ research productivity. Our results indicate that the DWC Project significantly increases both the quantity and the quality of research output among PhD students in supported disciplines, even after controlling for supervisor-related effects. In addition, these impacts vary significantly across institutional tiers and academic fields. Lower-tier universities experience considerable increases in publication volume with slight enhancements in quality, while top-tier institutions show no notable variation in either aspect. Disciplinary patterns also vary: Science and medicine show improvement in both measures, while engineering displays little change overall. These findings demonstrate how excellence initiatives influence human capital development via doctoral training and provide evidence-based recommendations for education policymakers aiming to maximize returns on strategic higher education investments worldwide.