The present invention discloses a square copper wire motor stator structure. The motor stator includes a stator core and a stator winding. The stator winding is disposed on the stator core, and the stator winding is a four-layer structure on the stator core. The stator winding is composed of square copper wires having square cross sections, and the stator winding comprises a first layer conductor,a second layer conductor, a third layer conductor and a fourth layer conductor from the outer circle to the inner circle of the stator in order. The stator winding is two sets of winding structures,the first layer and the second layer of conductors form a first set of windings, the third layer conductor and the fourth layer conductor form a second set of windings, the first set of windings is electrically isolated from the second set of windings, a dual-winding motor structure and different winding connection modes are utilized to achieve difference voltages and voltage distribution so as toimprove the redundancy and reliability of the system, and by using the square copper wires, the bare copper occupation rate in the tank and the motor power density are greatly increased.