Abstract: This paper is aiming at the geophysical difficulty for fluid prediction,especially for fluid prediction in fracture-cavity carbonate reservoir.Firstly,based on the modified Xu&White model for rock physics analysis of carbonate,P-wave and S-wave velocity prediction technical workflow was established,and effective analysis of elastic parameters for fluid identification was conducted.Research on fluid detection by prestack elastic parameters inversion and prestack fluid inversion evaluation technique were carried out based on carbonated rock physics analysis.Meanwhile,these methods were applied to Tahe Oilfield fracture-cavity carbonate reservoirs,and realized fluid detection and evaluation on fluid prediction.