Based on the data of innovation input and innovation output of 82 national high-tech zones from 2014 to 2018, the DEA-Malmquist index and Kernel density estimation method are used to study the spatial imbalance and the dynamic evolution of technological innovation efficiency in national high-tech zones. A couple of findings are presented as follows: ①During the observation period, the technological innovation efficiency of the national high-tech zones shows a continuous growth trend and a spatial difference. ②The technological progress rate of the national high-tech zones has turned from negative to positive, and the change in technical efficiency has turned from positive to negative. ③The spatial gaps of technological innovation efficiency growth in the overall, eastern, central, western, and northeastern national high-tech zones are clearly widening.