Conventional wisdom argues that environmental regulation can trigger both structural adjustments and enhanced innovation. We test this conjecture by using a difference-in-differences approach to analyze the impacts of China’s carbon emission trading (CET) pilot policy on energy consumption. We find that compliance with the CET regulation has triggered statistically significant adjustments in energy structure, industrial structure, and technological innovation. Adjustments in industrial structure also contribute to enhanced total factor energy efficiency, whereas increased technological innovation has mixed effects on energy efficiency. We show that in the short run, government-led innovation does not immediately contribute to improvement in energy efficiency, whereas enterprise-led innovation has a negative impact. It indicates that CET regulation can affect energy efficiency through industrial structure and technological innovation. Overall, our results provide new evidence for the strong version of the Porter hypothesis. Our results also provide strong scientific support for China’s recent transition towards market-based carbon mitigation strategies.