The establishment of the pilot free trade zones is a strategic measure to comprehensively deepen reform and expand opening-up under the new situation. Taking Shanghai, Tianjin, Guangdong and Fujian as examples, this paper uses counterfactual analysis to compare the difference between the economic real and counterfactual value before and after the establishment of the free trade zones to evaluate their effect on the regional economic growth. The results show that the establishment of the Shanghai, Guangdong, Fujian and Tianjin free trade zones promote the growth of GDP by expanding the trade and investment volume. That means the establishment of the free trade zones releases“institutional dividend”, and the reform effect is greater than the opening effect.