The invention provides a small liquid volume gas-liquid two-phase flowmeter, which comprises an electric four-way valve (or a valve bank substituting for functions of the four-way valve), a volume tube, an electric induction proximity sensor, a gas separation device, a reverse stabilizing device, a temperature sensor, a pressure sensor and a vortex precession flowmeter. The gas separation device is vertically arranged and is connected with an inlet pipe. The upper port of the gas separation device is connected with an output pipe through a pipe. The temperature sensor, the pressure sensor andthe vortex precession flowmeter are arranged on the pipe. The lower port of the gas separation device is connected with the inlet of the electric four-way valve through a pipe. The outlet of the electric four-way valve is connected with the lower end of the vertically arranged reverse stabilizing device through a pipe. The upper port of the reverse stabilizing device is connected with the outlet pipe through a pipe. The other two ports except the outlet and the inlet of the electric four-way valve are connected with the two access ports of the horizontally arranged volume tube through pipes. The invention has the advantages of convenient operation, low use cost, simple structure, low product price and high measurement accuracy.