The deviation between the actual processed blade and the designed blade shape inevitably occurs in the process of compressor blade manufacturing. Rotor37 was used as the research object and a three-dimensional steady Reynolds averaged Navier-Stokes simulation method was adopted in order to study the influence mechanism of blade thickness deviation on blade performance. The blade was parameterized and the blade thicknesses were increased or decreased uniformly, with changes of 0.06mm and 0.1mm respectively. Results illustrate that the blade thickness deviation affects the total pressure ratio, isentropic efficiency and stability margin of the single-stage rotor. Increasing the blade thickness will inhibit the transport of low speed airflow from blade root area to blade tip area along the radial direction. In the peak efficiency condition, this inhibit will cause low speed airflow to converge in the middle of the blade and increase the flow separation loss; while in the reference near stall condition, the inhibition of low speed airflow transport will weaken the accumulation of low energy airflow in the tip area, reduce the loss in the corner area, and expand the stable working range of the blade. Further, increasing the blade thickness causes the shock wave position to move backward and the shock wave intensity will decrease.