Abstract: The gas content is a critical parameter in resource calculation,and target selection and evaluation of coalbed methane.In the cases that the effective data of gas content are too few to meet the needs of research,it is an effective method for predict the gas content of coal seam in unknown area based on a few of measured gas content data,isothermal adsorption curves,reservoir pressure gradient,and moisture and ash yield data.The practice proves that the predicted gas content data are relatively close to the measured ones,ensuring the reliability of the results of resources calculation and evaluation.