In this work, concurrent modified constant modulus algorithm and decision-directed scheme with the Barzilai-Borwein method is proposed for blind equalization of wireless communications systems. The Barzilai-Borwein method, the two-step gradient method, is usually used to solve multidimensional unconstrained optimization problems. The proposed algorithm concurrently operates a modified constant modulus algorithm equalizer and a decision directed equalizer, it then adaptively adjusts the step size of the decision directed equalizer using Barzilai-Borwein method. Theoretical analysis is provided to illustrate that the proposed algorithm has a faster convergence speed, and better equalization performance than the original one. Simulation results support the new proposed technique.