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To promote gas extraction in low-rank high-gas coal beds, the pore structure characteristics of the coal and their effect on gas desorption were studied. The results show that micropores are relatively rare in low-rank coal;mesopores are usually semi-open and inkpot-shaped whereas macropores are usually slit-shaped. Gas desorption is relatively easy at high-pressure stages, whereas it is difficult at low-pressure stages because of the‘bottleneck effect’ of the semi-open inkpot-shaped mesopores. A ‘two-three-two’ gas extraction model was established following experimental analysis and engi-neering practice applied in the Binchang mining area. In this model, gas extraction is divided into three periods:a planning period, a transitional period and a production period. In each period, surface extraction and underground extraction are performed simultaneously, and pressure-relief extraction and conventional extraction are coupled to each other. After applying this model, the gas extraction rate rose to 78.8%.