An unmanned semi-submarine, including a main hull; airfoil buoyancy chambers; an antenna; a radar; a propeller; a rudder; and compartments. The airfoil buoyancy chambers include a front buoyancy chamber and a rear buoyancy chamber. The front buoyancy chamber and the rear airfoil buoyancy chamber are longitudinally distributed on the main hull. The radar and the antenna are disposed on the top end of the front buoyancy chamber. The rudder is disposed on the rear buoyancy chamber. The propeller is disposed at the tail of the main hull to drive the unmanned semi-submarine. The horizontal sections of the front buoyancy chamber and the rear buoyancy chamber are symmetrical airfoil. The compartments include a front equipment compartment, a rear equipment compartment, a control equipment compartment, a battery compartment, and a propelling compartment. The compartments are separated from one another using watertight walls.