In this letter, we propose a new technique that combines space time coding (STC) with pre-FFT multibeamforming for a multi-input multi-output (MIMO)-orthogonal frequency division multiplexing (OFDM) system. The proposed approach can effectively cancel a cochannel interference (CCI) while preserving the STC diversity and can mitigate the impairment of delay spread. The performance improvement of the proposed approach is investigated through computer simulation in a multipath channel with CCI.