Improving the total factor productivity (TFP) of manufacturing enterprises is crucial to the high-quality development of China's real economy. Based on the data of National Innovation Survey Enterprise Database of National Bureau of Statistics, this paper constructs a multi-time difference-in-difference model to study the impact and mechanism of the upgrading of the provincial high-tech zones on manufacturing corporate TFP. The main findings are as follows: Firstly, the upgrading of the provincial high-tech zones has increased manufacturing corporate TFP by 5.20 percentage points on average; secondly, the industry agglomeration and corporate tax reduction are the important mechanism adopted by the upgrading provincial high-tech zones to improve the level of the manufacturing corporate TFP; thirdly, compared with low efficiency manufacturing enterprises, the promotion effect of the provincial high-tech zone upgrading on the manufacturing corporate TFP of medium and high efficiency is more prominent. This paper provides empirical data reference and targeted policy suggestions for the government to promote the high-quality development of China's manufacturing industry by upgrading provincial high-tech zones.