Abstract: A low strength hetergeneity,high gas adsorpton and other featuresof the cal would make the consideration on the two speialissues of thesample preparaton and adsoption epul.run condito in the seepage exceriments with the coal and rock steady state method. /n combination with the previous experiment study results a detail iscussion was conducted that the briquete could replace the raw coal and the adsorption e ali.rum condion could be affeced to the permeabilitmeasurement.T'he paper hold that briquette sample would be a process to destouctre raw ceal porecrack stoucture and to be a reconstrucion ofthe simpe adistorionln order to more acually detect the coal and rock permeabltythe raw coal samples appied to the permeablity experiment were proposed. The acual calbed methanedrainage would be a degasing seepage state with an adsoption epaulirum steadiy broken.Before the adsorption epuillsrunm.the seepage measurement would be a gas-solid coupling infatable measuring method within the major cracks of the pemeability hole. nthe study on the coal and rock dsopio afictedtothe features of te gas seepage,before the adsorption equilbrium,the steady state seepage measuring method could not be recommended.