The invention discloses a garage prong exchanging carrier and a fire-prevention device. The garage prong exchanging carrier mainly comprises lifting and exchanging devices of with-support prong car-loading pallets, a chain with-rotary-shaft hooking and pulling device movable prong car-loading pallets and automatic fire-prevention curtain devices, wherein the chain with-rotary-shaft hooking and pulling device is used for parking and taking a car, the two ends of each movable prong car-loading pallet are provided with with-groove slide tracks correspondingly, and each parking-space entering and exiting port is provided with one automatic fire-prevention curtain device. According to the garage prong exchanging carrier and the fire-prevention device, lifting and exchanging parking and taking of the car are completed on the garage prong exchanging carrier, the structure is simpler, and failures of a garage are reduced; bearing main supports of parking spaces and four main supports of the garage prong exchanging carrier are all mounted near wheels of parked cars, and thus the bearing capacity of the garage is enhanced; and according to the garage provided with the garage prong exchanging carrier in a matched mode, a bus garage is especially suitable for being built in a matched mode, a garage structure is more scientific and reasonable, the car parking and taking speed is higher, installation and maintenance are easy, and the construction cost is lower than the construction cost of an original garage.