In this article, we combine a space-time block code (STBC) with a multi-carrier code division multiple access (MC-CDMA) system and a turbo code (TC) as channel code. MC-CDMA is likely to be one of the most promising access techniques for future wireless communication systems [N. Yee et al. (1993)] [M. Helard et al. (May 2001)]. In fact, MC-CDMA exploits the advantages of both the orthogonal frequency division multiplex (OFDM) multi-carrier modulation and of the code division multiple access (CDMA) technique. Moreover, the use of a multiple input multiple output (MIMO) OFDM system associated with a STBC code allows the achievement of both space and frequency diversities [J.-M. Auffray et al. (September)]. In this paper, we compare several STBC codes such as the Alamouti code [S. M. Alamouti et al. (October 1998)] and the generalized codes for 3 or 4 antennas proposed by Tarokh [ V. Tarokh et al. (July 1999)] applied to a MC-CDMA system leading to different spectral efficiencies. Then, since turbo coded MC-CDMA was demonstrated to be very efficient for a single input single output (SISO) system, allowing the use of a simple single user (SU) detector [M. Helard et al. (May 2001)], we extend this system to multiple input multiple output (MIMO) systems for different STBC. Simulation results are provided for full load systems.