This paper studies the dynamic mechanism of technological innovation diffusion from the dual perspectives of spread and driving mechanism of it. For the first time, the spread mechanism of technology innovation diffusion is put forward from the perspective of the spread mode of it based on innovation subject and innovation object, and its spread mechanism is measured by Bass model. The driving mechanism of technology innovation diffusion is put forward from the perspective of the driving factors of it around the innovation subject, the innovation object and the innovation intermediary, and the driving mechanism is measured by the spatial econometric model. Secondly, the ICT data of five categories of cities (288 cities at or above the prefecture level) in China from 2001 to 2018 were used to conduct an empirical analysis on the spread mechanism and driving mechanism of it. The results show that Bass model can effectively measure the spread mechanism of ICT innovation diffusion in five types of cities, and there are significant differences among the five types of cities. The fixed-effect dynamic SAR model of panel data can more comprehensively measure the driving mechanism of ICT innovation diffusion in five types of cities, The driving effect of time, space and space-time is significant. Meanwhile, the driving effect of five kinds of cities is measured and analyzed from the perspectives of macro, meso and micro, and a series of valuable research conclusions are drawn.