A gear pump comprising: a driving gear rotatable about a driving shaft (5b, 5c), and first and second driven gears respectively meshing with the driving gear to follow rotation of the driving gear; a housing accommodating the driving gear, the first driven gear and the second driven gear, and defining a flow path including first and second suction ports capable of sucking fluids, a first pressure port employing rotation of the driving gear and the first driven gear to pressurize and discharge the fluid from the first suction port, a second pressure port employing rotation of the driving gear and the second driven gear to pressurize and discharge the fluid from the second suction port; characterised in that a floating bearing supporting the driving gear so as to allow the driving gear to rotate about the driving shaft and being capable of floating along the driving shaft, and comprising a thrust face bearing a floating force exerted by the fluids along the driving shaft and first,, second and third pressure-receiving faces respectively oriented in a direction opposed to the thrust face; a first pressurizing chamber held between the first pressure-receiving face and the housing and having fluid connection with the first pressure port or the second pressure port to exert pressure on the first pressure-receiving face; a second pressurizing chamber held between the second pressure-receiving face and the housing and having fluid connection with the first suction port to exert pressure on the second pressure-receiving face,; and a third pressurizing chamber held between the third pressure-receiving face and the housing and having fluid connection with the second suction port to exert pressure on the third pressure-receiving face,. a driving gear rotatable about a driving shaft (5b, 5c), and first and second driven gears respectively meshing with the driving gear to follow rotation of the driving gear; a housing accommodating the driving gear, the first driven gear and the second driven gear, and defining a flow path including first and second suction ports capable of sucking fluids, a first pressure port employing rotation of the driving gear and the first driven gear to pressurize and discharge the fluid from the first suction port, a second pressure port employing rotation of the driving gear and the second driven gear to pressurize and discharge the fluid from the second suction port; characterised in that a floating bearing supporting the driving gear so as to allow the driving gear to rotate about the driving shaft and being capable of floating along the driving shaft, and comprising a thrust face bearing a floating force exerted by the fluids along the driving shaft and first,, second and third pressure-receiving faces respectively oriented in a direction opposed to the thrust face; a first pressurizing chamber held between the first pressure-receiving face and the housing and having fluid connection with the first pressure port or the second pressure port to exert pressure on the first pressure-receiving face; a second pressurizing chamber held between the second pressure-receiving face and the housing and having fluid connection with the first suction port to exert pressure on the second pressure-receiving face,; and a third pressurizing chamber held between the third pressure-receiving face and the housing and having fluid connection with the second suction port to exert pressure on the third pressure-receiving face,.