Abstract: In order to explore the development law of coal pore structure in syncline structure,taking the syncline structure in 1311S working face of changcheng No. 3 Coal Mine as the research object,the characteristics of coal pore structure were analyzed by low temperature nitrogen adsorption experiment which the coal samples were drilled from different positions in syncline structure region. The results show that the pore structure of coal sample in the syncline structure region shows regular distribution: the specific surface area and total pore volume gradually decrease from the axis to the two wings,while the average pore diameter increases gradually;the maximum pore sizes are all distributed around 2 nm,and the diameter of the maximum pore size in the syncline axis is less than that of the two wings;through the comparative analysis of the fractal dimension,the value of the fractal dimension increases linearly with the nearer the distance between the two wings to the oblique axis. Based on the analysis of the pore structure characteristics of coal samples in different positions of the same syncline,the development law of coal pore structure in the syncline structure is summarized.