In this letter, we propose an efficient near-optimal detectionscheme (that makes use of a generalized sphere decoder (GSD))for blind multi-user multiple-input multiple-output (MU-MIMO)systems. In practical MU-MIMO systems, a receiver suffers frominterference because the precoding matrix, the result of theprecoding technique used, is quantized with limited feedback andis thus imperfect. The proposed scheme can achieve nearoptimalperformance with low complexity by using a GSD todetect several additional interference signals. In addition, theproposed scheme is suitable for use in blind systems.