Exhaust structure of unmanned aerial vehicle engine

The utility model provides an exhaust structure of an unmanned aerial vehicle engine, and belongs to the technical field of unmanned aerial vehicles. According to the exhaust structure of the unmanned aerial vehicle engine, the engine comprises a crankcase, the crankcase is provided with a front end cover, the exhaust structure is characterized by comprising a vent valve, the vent valve is arranged at the upper end of the front end cover, and a separation device with a separation cavity is arranged in the crankcase; the front end cover is provided with an exhaust channel enabling the vent valve to be communicated with the separation cavity, and the separation cavity is communicated with an inner cavity of the crankcase. Gas containing engine oil particles is firstly filtered by the separation device for the first time, then the gas must be discharged upwards along the exhaust channel, and in the upward discharging process, the engine oil particles which are not filtered out by the separation device in waste c