Abstract: Rock young's modulus is an important parameter on making fracturing reconstruction scheme. By using the rock true triaxial compression testing data and ultrasonic testing data, through curve fitting, the relation between longitudinal wave and transverse wave has been obtained. Besides that, the relation among the dynamic young's modulus, static young's modulus and bulk density has also been calculated. In the end, the mathematical model of static young's modulus under conventional acoustic logging and density logging from upper Paleozoic reservoirs of Fuxian block has been established.