Abstract: Based on the test results of the primary wave (P-wave) velocities, shear wave (S-wave) velocities and elastic moduli of 51 core samples of basalt under saturated gas and water condition in the southern Leizhou peninsula, this paper studies the influence of porosity, pore types, lithofacies and fluids on the elastic mechanical parameters of rock and analyzes the sensitivity of petrophysical parameters for identifying the lithology and fluid content of basalt. The results show that in basalt, there are good linear relationships between P-wave velocity and S-wave velocity, as well as between density and P-wave velocity. There is a power function relationship between Young's modulus and density. Porosity is the main factor affecting the wave velocity in rock, and the effect of pore type on the wave velocity of rock cannot be ignored. Rock density is the most sensitive petrophysical parameter for distinguishing the sub-lithofacies of basalt. The cross plot of density versus Young's modulus can be used to identify the upper, middle and lower sub-lithofacies of flood basalt. The cross plots of the Poisson's ratio versus P-wave impedance and the ratio of Lame coefficient to shear modulus versus P-wave impedance can be used to distinguish gas-bearing zone and water-bearing zone in basalt.