Abstract: Taking the data of X and Y wells in Dabei-Keshen region as an example, the related formation rock mechanical parameters were calculated by using the array acoustic logging. The results show that the mudstone formation has high rock strength, followed by gypsum formation, and the sandstone has low formation strength. The higher the shale content, the greater the tensile, shear and compressive strength, and the lower the Biot coefficient. The method of array acoustic logging can accurately extract the time difference between the horizontal and vertical waves of strata, which has significant advantages in calculating the mechanical parameters of strata. The method can save expensive testing cost of elastic mechanical parameters and can predict and judge the development of deep strata.