This paper examines the impact of antenna selection on the performance of multiple input-multiple output (MIMO) systems over nonlinear communication channels. Analytical expressions are derived for evaluating the PWEP performance of space-time trellis codes over nonlinear MIMO channel, case of Rayleigh fading, when antenna selection is employed at the receiver side. Performance degradation due to nonlinearity in the channel is then estimated for the reduced-complexity system. Antenna selection is traditionally employed to optimize the performance/complexity tradeoffs in MIMO systems, over linear MIMO channels. It is shown in this work that the deployment of the scheme over nonlinear MIMO channel has the additional benefit of helping to cut back on the performance degradation due to nonlinearity in the channel. Our results show that the performance degradation due to nonlinearity in the channel reduces as less numbers of antennas are selected at the receiver, representing some savings in SNR penalty due to nonlinearity for the reduced-complexity system.