A multiuser cyclic shift differential chaos shift keying (MU-CSDCSK)communication system is proposed based on the high bit error rate (BER) caused by inter-symbol interference in the traditional multiuser differential chaos shift keying (MU-DCSK). The system divides the reference signal of MU-CSDCSK into N segments in accordance with number of users and transmits different users through cyclic shift period, using Walsh codes to ensure that the signals transmitted by each user are strictly orthogonal. Besides, in-depth analysis of multiple input single output multiuser cyclic shift differential chaos shift keying (MISO-MU-CSDCSK) is studied to further improve the performance of the BER. The BER formula in Rayleigh fading channels is derived and numerous simulations are completed. The simulation results show that the system can effectively improve BER performance, and it is of great value in application.