This paper uses a panel of 33 prices of industrial materials from 18 cities in China to provide an estimate of China's internal product market integration.We first define an inter-city price disparity variable,and then use Levin-Lin-Chu Panel Unit Root Test to test if inter-city price difference is convergent in the long run.The results are:(1)During the ten years,the price difference of most industrial materials became smaller and smaller,and six kinds of industrial materials have different pri...