The invention discloses a high-efficiency precise DC brushless motor. The motor comprise an outer rotor assembly, a circular magnet, an armature winding assembly, a laminated stator and a motor base assembly, wherein the outer rotor assembly, the circular magnet, the armature winding assembly, the laminated stator and the motor base assembly are sequentially installed on the same axis from the topto the bottom. The outer rotor assembly comprises a front end cover, a motor case and a rotating shaft, wherein the motor case and the rotating shaft are integrated with the front end cover in a mold-opening poured manner. The armature winding assembly comprises a hollow cup armature winding, a winding wire head connection board, and a terminal wire. The laminated stator is installed on a centralcylinder of the motor base assembly, and is formed by the lamination of a plurality of silicon steel pieces of a toothless groove structure. The motor base assembly comprises a flange, a baring, a gasket and a central cylinder disposed above the flange, wherein the bearing and the gasket are disposed in the flange. According to the invention, the assembly precision of the motor is improved, the assembly technology is simple and the cost is reduced. The operation of the motor is more stable, and the vibration and noise are reduced. Moreover, the utilization rate of space is higher, the reduction of the size of the motor is facilitated, and the power density of the motor is improved. The output efficiency of the motor is remarkably improved.