In the paper，we study the problems of information and efficiency in terms of market transactions． The main results include: 1) Presenting the conception of market information variety and information gathering and providing mathematical description of information gathering; 2) Setting up the living bargain model of imperfect market bargain games and Bellman equation of multiple transaction; 3 ) Proving market information gathering effect，which increases returns and raises market liquidity． That is the more important values and mechanism of market information，than only increasing resources dispose through solving multiple equilibrium and reducing transaction costs． It is also proved that information is not an abstractive market factor but internal value resource． Function of information can have some effect on efficiency and increase total values due to decreasing transaction time ( searcher time and bargain games) ．