In order to estimate whether the policy of carbon emissions trading can promote the green technology innovation of enterprises and verify the establishment of the "Porter Hypothesis" in China''s market-based environmental regulation reform. The difference-in-differences model (DID) and difference-in-difference-in-differences model (DDD) framework were used to analyze the sample data of A-share listed companies from 2006-2019. Three findings are found. First, the carbon emission trading policy can prove the "Porter Hypothesis", and the conclusion remains after the introduction of a series of robustness tests. Second, the carbon emission trading policy to promote enterprise green technology innovation mainly by the "leverage effect". Third, this promotion mainly exists in state-owned enterprises, large-scale enterprises and industries with high carbon emissions. Finally, the policy of carbon emissions trading also has played an active role in improving the quality of green innovation.