The invention discloses a method for assessing a laser shot peening effect. The method comprises the following steps: S1) determining the scope of the depth of the residual compressive stress layer required by the material; S2) sampling and performing surface polishing, thereby causing the flatness of the surface to be below 0.1 micron; S3) adopting high-power density nano-second pulse laser for performing laser shot peening treatment on the surface to be treated of the sample; S4) removing a restraint layer and measuring the depth d of the pit; S5) calculating and acquiring the depth Lp of the residual compressive stress layer according to the empirical formula of Lp=epsilon*d+c; assessing the laser shot peening effect, and if Lp is out of the optimal peening effect scope, altering the parameters and repeating S2 to S4 till Lp is in the optimal peening effect scope. According to the method provided by the invention, the laser shot peening effect is represented by measuring the depth of the pit of a laser shot peening prefabricated metal sample; the method has the characteristics of convenience and quickness; the basis can be provided for flexibly and quickly optimizing the laser shot peening parameters.