In recent years, more and more researchers in the control community have focused their attention on distributed coordination due to its broad applications in many fields, the consensus problem is well recognized as a fundamental problem in the cooperation control of multi-agent systems. In this paper, we discuss the noise problem of the discrete linear consensus protocol (DLCP) and point out that noise of DLCP is uncontrollable. A protocol using noise suppression function (NS-DLCP) to control the noise is put forward, the theorem about the reasonable range of the noise suppression function is vigorously proved, and sufficient conditions for noise controllable of NS-DLCP are further presented.