Abstract: Through analyzing another mode of the blind multi-user with LMS algorithm， a new algorithm based on least mean square (LMS) error is proposed in this paper. The new algorithm can get a faster convergence rate and a better SIR for the receiver of Blind MUD than the NLMS and the Algorithm proposed in the reference［5］.，the performance of the algorithm is comparable with the RLS and KALMAN to the synchronous CDMA system. At the same time， the SIR for the receiver is more stability.