Abstract: China's regulatory policies for vegetable industry since the 21st century can be divided into three categories:production policies, circulation policies, and other policies. Applying event study method, this paper seeks to investigate and evaluate the effects of regulatory policies on prices of vegetable products and their substitutes, and to test theexogeneity of the different policies of the vegetable industry by target positioning. Results show that 1) regulatory policies in the production process had positive influences on price increasing, and the duration of this effect can last for about 4months (from 1 month before implementation to 3 months after that); 2) regulation policies in circulation process also had positive influences on price increasing, but weaker and shorter than that from regulatory policies for production process;and 3) other regulatory policies only had limited positive influences, not enough to cause price increase. In general, allthe regulatory policies have not reached the expectations of the price increase for the vegetable industry in China in the21st century as designed. In order to stabilize the vegetable prices, this paper suggests that the Government should reduce policy interference to the market and let the market itself to play its role to regulate vegetable prices.