A low complexity punctured belief propagation(BP)detection utilizing channel puncturing for multi-user multiple-input multiple-output(MU-MIMO)systems is proposed in this paper.This paper constructs a cycle-free factor graph by puncturing certain non-zero entries in a transformed channel matrix,and proposes an adjusted BP algorithm with a more exact a posteriori message updating equation.The proposed algorithm converges rapidly in several iterations due to the cycle-free structure in the factor graph.Nevertheless,puncturing brings distorted noise and thus leads to performance degradation.To tackle this issue,this article further designs a layered detection with the help of maximum likelihood detector(MLD).Simulations demonstrate that the proposed detection algorithm achieves the identical performance to MLD with much lower complexity.