China’s economy has shifted from a high-speed growth stage to a high-quality development stage. Achieving green and sustainable growth driven by the digital economy is its most important purpose. Based on provincial panel data from 2013 to 2019, this paper examines the spatial heterogeneity of the digital economy (Dig) and its nonlinear impact on green economic growth (Geg) from multiple dimensions, using threshold models and spatiotemporal geographic weighting models. The study found that: (1) Dig can significantly promote Geg, but it presents a typical nonlinear characteristic: double thresholds with a trend of “weak negative → strong positive → weak positive”; (2) in this process, the three critical nonlinear factors are financial agglomeration (Fina) with a single threshold of “0.186” and the trend of “weak negative → strong positive”, the marketization level (Market) with double thresholds of “4.448 and 9.06” and the trend of “weak negative → strong positive → positive”, and green technology innovation (Grti) with double thresholds of “5.236 and 9.152” and the trend of “strong negative → strong positive → positive”; (3) the multi-dimensional composite threshold effect indicates that when 0.061 < Dig < 0.539, 5.236 < Grti < 9.152, 4.448 < Market < 9.06, and 0.186 < Fina, the digital economy has the greatest effect on the promotion of green economic growth; and (4) the spatial distribution regression results show that there is obvious regional heterogeneity. The paper has reference value in maximizing the promotion effect of the digital economy on green economic growth.

Under the background of “peak carbon dioxide emissions” and “carbon neutrality” strategy, it is urgent to explore whether China’s great efforts to continuously promote industrial low-carbon transition can promote high-quality economic development. Taking the implementation of low-carbon industrial parks pilot policy (LIPPP) as a “quasi-natural experiment”, this paper tries to answer this question. The results show that the LIPPP doesn’t significantly promote the sustainable-oriented high-quality development (SHD) of the economy, but mainly boosts the value-oriented high-quality development (VHD), which is characterized by being obviously biased towards the technological progress. The policy effect is more obvious in the central region and cities with a relatively poor natural resource endowment. The mechanism analysis shows that the LIPPP promotes the VHD of the economy through the innovation incentive effect and the capital deepening effect. The technological progress related to the VHD promoted by the LIPPP has a crowding out effect on that of the SHD. In addition, regional innovation, capital deepening, and energy transformation all play a certain role in promoting the SHD, but which is overshadowed by the effect of the VHD promoted by the LIPPP. This paper provides policy implications for China to promote high-quality economic development in the process of low-carbon transition.