The invention discloses an ejection type protection device for emergency crash of a multi-rotor unmanned aerial vehicle, belongs to the technical field of unmanned aerial vehicle protection, and aimsto solve the problem of high economic loss after crash of the unmanned aerial vehicle due to the fact that a crash-free protection device exists in the prior art. The ejection type protection device comprises an ejection part and n groups of recoil parts, wherein the ejection part comprises an ejection sliding cylinder, a steering engine set, an ejector and a speed reduction device; one end of theejection sliding cylinder is fixed on the multi-rotor unmanned aerial vehicle through a fixed ring seat; the steering engine set is fixed on the fixed ring seat; the ejector is arranged in the ejection sliding cylinder, and is controlled and limited at one end, close to the fixed ring seat, in the ejection sliding cylinder or is ejected towards the other end through the steering engine set; the speed reduction device is arranged on the ejector, and is driven by the ejector to retract or eject the ejection sliding cylinder; each group of recoil parts comprises two pairs of recoil structures which are symmetrically arranged on two rotors of the multi-rotor unmanned aerial vehicle; each pair of recoil structures comprises two traction legs which are arranged on one rotor and are oppositely arranged; and each traction leg is provided with a recoil device.