This paper addresses the formation control problem of a multi-agent system (MAS) under the leader-follower scheme. Thus, the followers must to keep a desired relative distance with respect to the leader trajectory against known and constant communication delay. Thus, in order to ensured the coordinated behavior and formation control against parametric uncertainties and external disturbances, a decentralized control approach based on a state predictor and a Second Order Sliding Mode control is proposed. Sufficient conditions are provided to guarantee the stability of the closed-loop system. Finally, simulation results illustrate the effectiveness of the proposed method.