In this paper, the performance of a bit-interleaved space-time trellis coding (BISTTC) scheme is investigated for orthogonal frequency division multiplexing (OFDM) systems utilizing multiple antennas. The BISTTC scheme considered here concatenates the outer code with the well-known space-time trellis code (STTC) through a bit interleaver. Compared to existing concatenation of BICM with space-time block code (STBC), BISTTC has significant performance advantage in applications with low spectral efficiency and simple outer code, due to its ability to exploit available diversity resources more efficiently.