Relay transceiver processing for multiuser two-way communications is optimized based on zero-forcing (ZF) and minimum mean-square-error (MMSE) formulations under relay power constraints. Cochannel interference (CCI) frommultiusers and self-interference (SI) from two-way communications are efficiently mitigated by the proposed relay processing with multiple antennas. The system performance is examined in relation to the system BER by computer simulation. Numerical results indicate that the beamforming method is more attractive than the spatial multiplexing method for the two-way communications.