Abstract:The 14th Five Year Plan clearly points out the need to promote the deep integration of the digital economy and the real economy. This article empirically tests the economic growth effect of the digital economy through mechanism analysis and the construction of a PLSTR model. Research has found that: firstly, there is a significant scale bottleneck effect in the driving effect of the digital economy on economic growth. When the number of broadband connections in a province reaches 22.09 million, the scale of the digital economy will tend to saturate; Secondly, in provinces in the early stage of digital construction, economic growth exhibits a "human driven" characteristic. As the development of the digital economy crosses the threshold of scale, the dividends of the digital economy gradually fade, and economic development will enter a low-speed growth stage of "resource driven"; Thirdly, at present, the vast majority of provinces have reached the bottleneck of digital economic growth, and must integrate new technologies and industries to improve the efficiency of the digital economy. This is also an important exploration direction for future digital industrialization and industrial digitization.

Keywords:digital economy;technological innovation;regional economic growth;PLSTR model;scale bottleneck