On the basis of physiscal properties of diatomite, a great abundance of logging data and chemical analyses of core samples from the Xianfeng lignite basin have been examined, which leads to the establishment of a method for dividing grade of diatomite and the determination of correlation indicators for logging curves. The application of logging curves in such aspects as qualitative identification of ore beds, measuring their thickness and dividing their grade, correlation of ore-bearing strata and analysis of sand as well as day content has been proved to be effective to some extent.