Abstract: The folded structure is an important factor influencing the safe production of a coal mine. The cognition results of the predecessors on the folded structures in Xiayukou Mine can not meet the needs of current mine production.For this purpose, quantitative analysis was carried out on the overall form of this mine and the development characteristics of the folded structures by using the trend surface analysis and according to the newly revealed geological data. The research results proved that the predecessors'judgment on the undulation form of the whole strata of Xiayukou Mine and the large folded structure on the Beishanzi syncline was accurate, but there were large errors in the judgment of small folded structures in the mine. The new cognition of the mine folded structures based on the trend surface analysis can provide new geological basis for the future production of Shangyukou Mine.