Abstract: Low-temperature nitrogen adsorption method(LINAM) is used to detect the micropores of 26 coal samples,and the experimental results are analysed in this paper.The detectable minimal pore by LINAM is 0.6 nm in diameter,which benefits the research on micropore in coal.The pore between 0.6 and 10 nm in diameter is with more specific surface area than the pore between 10 and 10 0 nm in diameter,so the former plays a more important role than the latter.More attention should be paid to the absorbed methane,and the contents of free methane and adsorbed methane are fewer than the contents usually understood.