The invention discloses a multifunctional turbofan jet engine which includes a fan, a gas compressor, a second combustor, a turbine and an exhaust nozzle, wherein the fan is used for sucking air, the gas compressor is used for doing work on the sucked air, the second combustor is used for igniting gas on which the gas compressor does work, and the exhaust nozzle is used for exhausting the combusted gas. The multifunctional turbofan jet engine further comprises a first combustor, a first splitter plate and a second splitter plate, wherein the first combustor is arranged in front of the second combustor, the first splitter plate and the second splitter plate are used for splitting gas, the first splitter plate and the first combustor are correspondingly arranged, the second splitter plate and the second combustor are correspondingly arranged, and the first splitter plate and the second splitter plate are respectively provided with a travel switch I and a travel switch II which are used for rotating the corresponding splitter plate. The invention aims to provide the multifunctional turbofan jet engine which has the advantages of inlet air cooling, accurate gas splitting, balanced ignition, uniform-velocity starting, level-changing acceleration, high-efficiency, safety, thrust vectoring, easy operation and versatility.