The invention provides a multifunctional butt joint device for a double-pulse engine. The device comprises a frame, a lifting mechanism, hoop assemblies, a pressing device, a transverse moving mechanism and a supporting guide rail, wherein the supporting guide rail is arranged on the frame, and the lifting mechanism can move along the supporting guide rail; the hoop assemblies are arranged on thelifting mechanism through the transverse moving mechanism and horizontally moves in a manner of being perpendicular to the supporting guide rail, and rolling wheels are arranged on the hoop assembliesto drive the engine arranged on the hoop assemblies to rotate in the axial direction of the engine; and at least two hoops are used for fixing one stage of engine body, the two stages of engine bodies are adjusted to be coaxial with each other through the lifting mechanism and the transverse moving mechanism, and the pressing device adjusted to be coaxial with the engine is used for pushing the two stages of engine bodies to be in butt joint with each other. According to the device, the butt joint precision is high, the rapid movement is achieved, the rapid butt joint is achieved, the labor intensity is reduced, the utilization rate of the device is high, the cost is saved, and the production efficiency is improved.