The invention aims to provide a propane liquid gas micro propulsion device suitable for a micro-nano satellite. The device comprises an exhaust valve, a first propellant storage box, a second propellant storage box, a first heat-conducting module, a second heat-conducting module, a pressure reducer, a buffer tank, a safety valve, a thruster, a pressure sensor A, a pressure sensor B, a filter and a control circuit box. Propane serves as a propellant in the micro propulsion device, so the micro propulsion device is non-toxic and pollution-free; the micro propulsion device has the advantages of simple structure, low quality, low power consumption and high reliability; mounted on a mounting partition board, the micro propulsion device is convenient to be mounted and replaced; and because of no excessive relation and interference with other parts of the satellite, the micro propulsion device is convenient to be replaced and maintained.