The Research Of Price Difference Between A-share And B-share

China securities market were built, develop, expanded rapidly in a special complex-economic structure in the last twenty years and the over twenty trillion RMB market capitalization is attracted worldwide attention. B-share market as one of the important leftover problems has been waiting to be dealt with by our supervision department.The investors in B-share market always take more concern about the B-share discount and its development in future. The purpose of research in this paper, is seeking out the actual reason of B-share discount and try to get some enlightenment for the unification of A-share and B-share. Based on the conclusions of formers, the theoretical principles and analysis of B-share discount, we processed the trading data of35different of dual-listed companies in Shanghai securities market and34different of dual-listed companies in Shenzhen securities market for8years, created the multiple regression equation. By the regression analysis of panel data, we got some inference about the factors of liquidity difference, demand elasticity difference, investment theory difference, interest rate, main investors difference that significance cause the B-share discount. And the main investors difference is a very important factor especially.Meanwhile the paper was being written. More and more B-share companies announced their Programs of B shares transfer. Repurchasing, changing to issue H-Share. changing to issue A-Share, B-share transfer A-share directly, delisted. Hope that B-share, a obsolete product of history, will be given a new life by some ways in the near future.