The invention discloses a fully automatic cutting machine, which comprises a frame, a control box and a protective shell. The frame is provided with a bottom plate, and the bottom plate is provided with a cutting device, a driving device, a feeding device, a guiding device and an adjusting device; The cutting device includes a cylinder holder, a cutting cylinder and a knife holder, the cutting cylinder is installed on the cylinder holder, and the cutting cylinder is connected to the knife holder; the driving device includes a support, and a stepping motor is installed on the support; The feeding device includes a feeding base plate, a connecting plate is fixed on the feeding base plate, the connecting plate is connected to the cylinder fixing plate, the cylinder fixing plate is installed and fixed with a cylinder, the cylinder is connected to the guide rail, the bottom end of the guide rail is connected to the moving conduit, and the moving conduit is covered with an optical axis. The optical axis passes through the cutting device, the driving device, and is mounted on the guiding device. Compared with the prior art, the present invention has the advantages that: the structure of the present invention can realize the mechanical cutting of rubber hoses for air conditioners, save manpower, increase production capacity, and reduce product defective rate, and at the same time, the cuts are neat and beautiful.