Amid global scientific and technological (hereinafter “sci-tech”) competition and China’s innovation-driven strategy, achieving high-quality sci-tech innovation (HQDSTI) is crucial for economic transformation but faces challenges such as resource mismatch, insufficient funding, and low commercialization efficiency. Using panel data from 35 major Chinese cities (2013–2022), this study distinguishes between public sci-tech finance (PSTF) and market sci-tech finance (MSTF) and employs benchmark regression, mediation, and threshold models to investigate their impacts on HQDSTI. Results show that: (1) Both PSTF and MSTF significantly promote HQDSTI, with stronger effects in coastal, dual-center, and pilot cities, and in regions with low fiscal decentralization. MSTF is more effective under high marketization, while PSTF and overall STF are more effective under high financial development. (2) Industrial upgrading serves as a positive mediator, whereas venture capital exerts a suppressive mediating effect that intensifies as its scale expands. The promoting effect of industrial upgrading weakens beyond the threshold level. (3) Policy recommendations include differentiated financial strategies: fostering market-oriented instruments in coastal cities, optimizing targeted support in inland areas, strengthening regional and public–market financial coordination, and improving mechanisms of industrial upgrading and venture capital. This study provides theoretical insights for enhancing the synergistic effect between sci-tech finance and high-quality innovation development. • Distinguish public and market sci-tech finance, explore synergistic effects and differential impacts. • Develop a multi-dimensional evaluation framework for assessing high-quality sci-tech innovation. • Examine heterogeneity across five analytical dimensions to uncover regional and structural variations. • Reveal intermediary roles of industrial upgrading and venture capital. • Identify threshold effects and define the effective range of sci-tech finance.
JIN et al. (Wed,) studied this question.