A full-circumferential flow pump includes an outer cylinder and a motor housed in the outer cylinder. The motor has a motor frame, a stator disposed in the motor frame, a main shaft, a rotor mounted on the main shaft and rotatably disposed in the stator. The outer cylinder defines an annular space defined around the motor frame, the outer cylinder having a pump suction port defined therein for introducing a fluid therethrough into the annular space. A pump unit is mounted on an end of the main shaft, and the outer cylinder has a discharge window defined therein for discharging a fluid from the pump unit. A discharge case is mounted on an outer circumferential surface of the outer cylinder in communication with the discharge window, the discharge case having a pump discharge port.