Abstract: in order to soive the low drainage recovery rate problem of the conventional caled methane development technique.the CO2 injecion in the seam could inprove the drainage recovery rate and could realie the geolgical depostton of CO2.Fronm the CO2 physical parameters the micro porefeatures of the cal and ro:k.the seepage lav of the seam.adsorpion and solution of the coal nd rock staility of the coal and rock mechanics,the volume defomation and others,the paper stacedthe study progress on the interaction between the CO2 and sean at home and abvoad.Acording to the CO2 easy toreach the supecirticalstate in the underground mine in combination with the stuty methods under the CO2 gas staeat home and abvoad.,the paper pointed out that the CO2 in the supercirtialstae affic1ed to the coupling of the seam adsorption-seepage- mechanic-defomation property would be the future studly orientation. The paper proided the key problens to be solved in thecoalbed methane development with the application of the supercritical co2.