The progress of green technology plays a crucial role in improving carbon emission efficiency, while the role of environment-related incentives and constraints policies on green transition cannot be ignored. A threshold effect model is constructed using provincial panel data from 2006 to 2020 to examine the relationship between green technology progress and its impact on carbon emission efficiency. The results show that environmental policies can effectively influence green technological progress, but there is a double threshold effect, and the impact of green technological progress on carbon emission efficiency shows a marginal decline when environmental policies reach a certain threshold. Therefore, utilizing good policy tools at different development stages can effectively enhance green development efficiency, which provides new insights into the green and low-carbon transformation of the regional economy.