The invention relates to a device for separating methane from oxygen-bearing coalbed methane, and belongs to the technical field of oxygen-bearing coalbed methane processing. The device comprises a striping tower, an evaporator, a heat exchanger, a flow regulating valve and a tail gas compressor, wherein the striping tower and the evaporator are used for jointly completing the separation of methane in the oxygen-bearing coalbed methane; the heat exchanger is used for heat exchange between cold materials and hot materials; the flow regulating valve is used for regulating the flow of materials and reducing the pressure and temperature of the materials; and the compressor is used for pressurizing the materials. The device can work under a relatively low operating pressure, is simple in process, good in safety and reasonable in use of cold energy, is simple and convenient to operate and has strong working condition adaptability and high recovery rate of methane.