The invention provides a gas-liquid mixing pump. The gas-liquid mixing pump comprises a pressure gauge, an air intake duct, an automatic control mechanism, an air intake, a connecting pipe, an air chamber, a first pressure measuring port, a pressure meter, a second pressure measuring port, a pressure transducer, a liquid inlet, a liquid outlet, a stirring wheel, a bearing, a gearbox and a motor; the pressure gauge is arranged on the air intake duct and the air intake duct is connected to the automatic control mechanism; the air intake is arranged below the automatic control mechanism, and the automatic control mechanism is connected to the first pressure measuring port and the second pressure measuring port in order by the connecting pipe; the pressure meter is arranged above the first pressure measuring port with connection, and a connecting base is arranged below the first pressure measuring port with connection; the pressure transducer is arranged above the second pressure measuring port with connection, and a connecting base is arranged below the second pressure measuring port with connection; the motor is connected to the gearbox, the bearing and the stirring wheel in order; the liquid inlet and the liquid outlet are arranged at the left side of a pump case. The gas-liquid mixing pump has the beneficial effects that air input can be accurately controlled according requirements of different mixed liquors and self-adjustment of air pressure in the operation process is realized, the air pressure is constant, so that fully mixing of gas and liquid is realized and scrubbing effect is improved.