Effected by spatial difference and types of environmental regulation, enhanced environmental regulation does not necessarily lead to reduce net carbon emissions (NCE). Based on panel data of 30 province-level administrative regions in China from 2003 to 2018, this paper analyzed the impact of heterogeneous environmental regulations on NCE using geographically weighted regression (GWR). The results showed that (1) the total NCE of each province in China presented an increasing trend followed by fluctuation, with obvious spatial aggregation characteristics. (2) The intensity of four environmental regulations, command-and-control (CAC), market-incentive (MI), public-participation (PP), and voluntary environmental program of firm (VEPF) tended to increase slightly over the study period with decreasing spatial heterogeneity. (3) CAC environmental regulations had a “green paradox” effect on NCE, meaning an improving CAC environmental regulation would surprisingly increase its negative effects and contribute to NCE growth. The effect of MI environmental regulation on NCE shifted from overall promotion to partly promotion and even suppression. PP and VEPF environmental regulation would reduce NCE. The suppressive effect of PP environmental regulation grew over time, while VEPF did not. Finally, based on the research conclusion, some policy suggestion are proposed for differentiated management, diverse system of governance, and collaborative governance.