Abstract: The theory of evidence is important for solving uncertain problem，the evidence using in the evidence theory is given by experts.The expert’s knowledge is limited，subjective and sometimes difficult to obtain.Dempster has offered a algorithm of evidence combination，but the algorithm need independent evidence.If it is used in high conflict evidence，the result would be innormal.To solve these problems，this paper presents the algorithm of evidence theory which draws into the concept of attribute dependability of rough sets，utilizes it to weigh the evidence importance，and can combine highly conflicting evidences more satisfactory.From the results，this method avoids the subjective ingredient influence，so it improves the precision of fusion result and obtains real conclusion.