Abstract: 3 tunable parameters are used to control the construction of wavelet basis function, allowing the wavelets to better match with seismic signals and in favor of obtaining more accurate time-frequency analysis results, which is an effective method to identify thin reservoirs. Theoretical research and composite signal spectrum analysis prove that the high-precision three-parameter wavelet spectrum analysis method can effectively improve the identification precision of thin reservoirs because it focuses on high-frequency energy and has high resolution. The combination of the method with the non-linear e-index attenuation gradient matching highly improves the accuracy of frequency attenuation gradient calculation and the reliability of fluid property identification results. The combined method is applied in the reservoir prediction and fluid property identification of Ⅳ section of the second member of Zhuhai formation, Wenchang A oilfield in the western South China Sea, and the prediction results are in accordance with the actual drilling status. The effective application of the method has improved the potential tapping of Wenchang A oifield and is helpful for oil recovery enhacement