As China’s economy has entered a stage of high-quality development, enhancing new quality productivity has become a crucial pathway for promoting regional coordination and innovation-driven growth. This study demonstrates that the Pilot Free Trade Zone (PFTZ) policy in China significantly promotes highquality economic growth by improving the urban New Quality Productivity Index (NQPI). Using a balanced panel dataset of 271 prefecture-level cities from 2009 to 2022, we construct a multidimensional, entropy-weighted NQPI covering labor quality, labor input, and labor capital. The study employs a staggered Differencein- Differences framework, supplemented by event-study and triple-difference models, to assess policy effects. Results show that the establishment of PFTZs increases the NQPI by about 2% on average, with policy effects compounding across successive pilot waves. Earlier cohorts exhibit lagged responses, while later cohorts—particularly Hainan in 2018—show immediate and significant improvements. Heterogeneity analysis further reveals that the policy’s impact is more pronounced in cities with strong net population inflows, unconventional industrial structures, major transport hubs, and provincial or first-tier status.