The invention discloses a fire protection and extinguishing device based on an unmanned aerial vehicle and belongs to the technical field of fire protection and extinguishing.The fire protection and extinguishing device comprises a rack, a flight hoisting mechanism, a fire extinguishing bomb fixing mechanism and a fire extinguishing bomb releasing mechanism; the rack comprises rack arms, a fixing frame and a foot stand, the rack stretches out of the rack arms along a rack body, and the lower portion of the rack body is provided with the fixing frame and the foot stool; a motor-controlled propeller of the flight hoisting mechanism rotates at different rotation speeds, and the periphery of the propeller is provided with a protection hood; a hoop of the fire extinguishing bomb fixing mechanism is connected with the fixing frame to jointly fix fire extinguishing bombs; first pins of the fire extinguishing bomb releasing mechanism are inserted into bottlenecks of the fire extinguishing bombs, and an electromagnetic unit controls the first pins to be pulled out to release the fire extinguishing bomb.The fire protection and extinguishing device can play a good role in monitoring fire protection in complex fire scenes such as a city high-rise building and forests, fire scene information is positioned efficiently and accurately with low cost, meanwhile the purpose of extinguishing fire rapidly can be achieved, information of trapped personnel can be obtained flexibly, and it is convenient to apply and popularize the fire protection and extinguishing device.