The utility model provides an independently air crash device is prevented to unwrapping wire based on unmanned aerial vehicle, including unmanned aerial vehicle, be provided with control module in unmanned aerial vehicle, unmanned aerial vehicle's below sets up a haulage rope cutting device, haulage rope cutting device includes the round tube, a tension sensor, elasticity leather strap and cuttingdevice, force sensor sets up the blind end department at the round tube, elasticity leather strap one end is connected with force sensor, the other end is connected with the haulage rope, cutting device includes electric putter, the cutting knife, cutting backup pad and haulage rope restraining mechanism, force sensor and electric putter all are connected with control module. Receive when hindering when the haulage rope, this system can utilize the cutting knife to cut off the haulage rope in the very first time, has maximumly shortened the haulage rope time of coming off to greatly reduced the possibility of unmanned aerial vehicle air crash.