As the most leapfrog reform of China’s market-oriented exchange rate reform, exchange rate regime reform in 2005 occupies a significant position in the continuous growth of China’s export trade after its accession to the WTO. Optimal control group is chosen by using 20 countries and regions from 1995 to 2015 and the synthetic control method is adopted for counterfactual analysis, this paper empirically evaluates the impact of the market-oriented reform of the RMB exchange rate regime in 2005 on China’s export trade. The evidence shows that: the market-oriented reform of the exchange rate regime from dollar peg to managed float has a significant positive effect on export trade, the growth rate of export technology complexity increased by about 1.83‰ , and its effects are heterogeneous, which inhibites the export of primary products and resource-based products, and promotes the increase of the export technology complexity of medium and high-tech products. The market-oriented reform of the exchange rate regime is also an important part of the internationalization of the RMB; meanwhile, it is expected to promote China’s export trade to achieve the goal of stabilizing foreign trade.