Abstract: A gas-liquid mixing control system includes a liquid supply unit, a liquid pressure regulating valve, a gas supply unit, a gas pressure regulating valve, a mixing tank, an output pipe, and a non-electric control flow regulator. The mixing tank communicates with said regulating valves; liquid and gas are mixed in the mixing tank to form mixed fluid. The first end and second end of output pipe communicate with the mixing tank and the machine respectively, making mixed fluid output from mixing tank to machine through the output pipe. The mixed fluid in first end and second end have third flow and fourth flow respectively. Said flow regulator communicates with the output pipe; the mixed fluid passing through said flow regulator has fifth flow. The first flow is not lower than at least one of the fourth and the fifth flow. Additionally, a control method for gas-liquid mixing is disclosed.