The invention discloses an active vine cutting machine. The active vine cutting machine comprises a connecting frame, a driven shaft, blades, a gearbox, a machine frame, a speed reducer and a driving shaft, and is characterized in that the driving shaft is installed on the machine frame, one end of the driving shaft is installed on the gearbox through bearings, the other end of the driving shaft is installed on the connecting frame through bearings, the speed reducer is installed on the driving shaft, one end of the driven shaft is installed on the gearbox through bearings, the other end of the driven shaft is installed on the connecting frame through bearings, the blades are installed on the driven shaft, the speed reducer, the driving shaft, the gearbox and the driven shaft form a transmission mechanism of the vine cutting machine, and the driven shaft and the blades form an execution mechanism of the vine cutting machine. The active vine cutting machine is connected with a four-wheel tractor and can cut off intertwined sweet potato vines, thereby effectively saving labor, reducing cost and improving working efficiency; besides, the active vine cutting machine is simple in structure and convenient to operate.