A manufacturing method of a three-phase motor structure comprising: providing an inner flange of an outer stator ring frame with at least one first engaging portion, the outer stator ring frame having an inner circumferential flange surrounding a longitudinal axis to form an axial hole, providing a series of detachable pole tooth units, with each of the detachable pole tooth units including at least one second engaging portion, the outer stator ring frame and the pole tooth units being made of magnetically conductive materials, the inner flange of the outer stator ring frame corresponding to the pole tooth units, winding a plurality of wires on the series of detachable pole tooth units to provide a plurality of windings thereon; assembling the series of detachable pole tooth units with the plurality of windings thereon with the outer stator ring frame to form a sectional stator by engaging the at least one second engaging portion with the at least one first engaging portion for assembling, wherein the assembling comprises providing magnetic conductive materials between the at least one first engaging portions of the outer stator ring frame and the at least one second engaging portions of the pole tooth units; attaching a printed circuit board to a predetermined position of a side of the sectional stator; welding wire connection ends of the plurality of windings to contact points (21a, 21b, 21c) provided on the printed circuit board; and forming assembling marks of the contact points on the printed circuit board by forming assembling marks "U", "V" and "W" on the printed circuit board provided for the contact points of U, V and W phases of the three-phase motor structure. providing an inner flange of an outer stator ring frame with at least one first engaging portion, the outer stator ring frame having an inner circumferential flange surrounding a longitudinal axis to form an axial hole, providing a series of detachable pole tooth units, with each of the detachable pole tooth units including at least one second engaging portion, the outer stator ring frame and the pole tooth units being made of magnetically conductive materials, the inner flange of the outer stator ring frame corresponding to the pole tooth units, winding a plurality of wires on the series of detachable pole tooth units to provide a plurality of windings thereon; assembling the series of detachable pole tooth units with the plurality of windings thereon with the outer stator ring frame to form a sectional stator by engaging the at least one second engaging portion with the at least one first engaging portion for assembling, wherein the assembling comprises providing magnetic conductive materials between the at least one first engaging portions of the outer stator ring frame and the at least one second engaging portions of the pole tooth units; attaching a printed circuit board to a predetermined position of a side of the sectional stator; welding wire connection ends of the plurality of windings to contact points (21a, 21b, 21c) provided on the printed circuit board; and forming assembling marks of the contact points on the printed circuit board by forming assembling marks "U", "V" and "W" on the printed circuit board provided for the contact points of U, V and W phases of the three-phase motor structure.