Abstract: In oil and gas development, the study of dynamic and static elastic modulus transformation relationship of rock is very important for the evaluation of reservoir compressibility and fracturing effect. In this paper, we use 23 rock samples from 4 coring wells in CA area to carry out P-wave and S-wave measurements and triaxial stress tests, and the relationship between P-wave and S-wave time difference, longitudinal wave time difference and volume density was established. On this basis, the transformation relationship model of dynamic and static elastic modulus was established. Six samples not involved in modeling were used for precision comparison and reliability analysis. The calculated static Young's modulus and Poisson's ratio were distributed along the 45° diagonal line with the experimental measured values. The average absolute error of the calculation of static Young's modulus was 0.623 GPa, and the average absolute error of the calculation of Poisson's ratio was 0.022. It shows that the accuracy of dynamic and static elastic modulus conversion relationship established in this experiment meets the production needs and provides technical support for evaluation of formation compressibility and design of reasonable fracturing scheme.