In this paper, an efficient unlinkable, divisible electronic cash based on bit commitment scheme is proposed. The complexity of every protocol in our scheme is O(logN), where N is the precision of divisibility, i.e., N=(the total cash value)/(minimum divisible unit value). This scheme overcomes the problems of previous schemes through its greater efficiency and the real unlinkability of every cash it generated. We also proved the security of the proposed cash scheme under some clarified cryptographic assumptions.