Abstract: The distribution of gas reservoirs in Chaiwopu block was not significantly affected by the structure, but mainly controlled by the lateral distribution of sand bodies and the changes of reservoir properties. It belongs to the lithologic gas reservoirs under the tectonic background, and has strong heterogeneity, poor continuity and the reservoir prediction accuracy is not ideal. Therefore, a flexible and convenient method needs to be developed to describe the complex non-uniform media. Through small-scale fractal dimension of multiwell logging facies, the obtained distribution trend of the small-scale contour plane is in good agreement with the actual gas content distribution, and then by means of the technique of log phase fractal characteristic spectrum, the reservoir distribution regularity can be predicted. In combination with seismic data, the horizontal distribution regularity of large strata can be predicted, which can further improve the accuracy of reservoir prediction.