China’s innovation is transforming from quantity-oriented to quality-oriented. It is of great significance to study its mechanism, characteristics and laws. Based on the quantity and quality of innovation, this paper establishes a new analytical framework to study the innovation upgrading from a dynamic perspective, and takes China’s high-tech industry as an example to conduct an empirical study by using panel data model and panel threshold model. The results show that the innovation and upgrading of high-tech industry mainly includes quantity priority upgrading and quality priority upgrading. Quality first innovation upgrading can save more time. At present, China is still in the accumulation stage of innovation upgrading. For the quantity priority upgrading, R&D personnel plays a greater role, and for the quality priority upgrading, R&D funds play a greater role. Knowledge spillover has a significant impact on quantity priority upgrading, and innovation accumulation has a significant impact on quality priority upgrading. The contribution of R&D funds to innovation quality has the threshold effect of R&D investment and innovation quality. The contribution of R&D funds to innovation quality has knowledge spillover threshold effect.