A pre-processing blind multiuser detection al go rithms based on the least squares constant modulus (P-LSCMA) using antenna arra y is proposed in this paper. It first uses the signals received from every anten na to correlate with the conjugation of the DoA vector of the expected user, and then applies the pre-processed signals to the LSCMA. We simulate and compare t he proposed algorithm with the conventional LSCMA. Simulation results show that the proposed algorithm is superior to LSCMA. A pre-processing blind multiuser detection al go rithms based on the least squares constant modulus (P-LSCMA) using antenna arra y is proposed in this paper. It first uses the signals received from each anten na to correlate with the conjugation of the DoA vector of the expected user, and then applies the pre-processed signals to the LSCMA. We simulate and compare t he proposed algorithm with the conventional LSCMA. Simulation results show that the proposed algorithm is superior to LSCMA.