A method for inserting insulating sleeves into wiring slots of a flat wire motor stator, comprising the steps: S1: selecting a plurality of said insulating sleeves matched with a size of wiring slots of said flat wire motor stator, and pre-processing the insulating sleeves to a length by cutting according to a size of the flat wire motor stator; S2: fixing the flat wire motor stator into a positioning plate set of a production line among two or more production lines; S3: placing the pre-processed insulating sleeves into a feed mechanism of said production line, and conveying the pre-processed insulating sleeves through a conveying mechanism of said production line to a positioning mechanism of said production line, said positioning mechanism located behind the conveying mechanism; S4: clamping and transmitting, by a clamping mechanism, the insulating sleeves from said positioning mechanism to a position above the wiring slots of the flat wire motor stator; S5: moving a guide plate of a guide mechanism of said production line to a position above the flat wire motor stator in the positioning plate set, wherein S5 is synchronized with S4; S6: inserting the insulating sleeves into the wiring slots of the flat wire motor stator through said guide plate; S7: fully inserting the insulating sleeves into the wiring slots of the flat wire motor stator by a leveling mechanism; and S8: removing the flat wire motor stator, and putting in another flat wire motor stator; resetting these mechanisms, and repeating S1 to S7; wherein each of said production line runs steps S1 to S8, wherein in step S6 said insulating sleeves are inserted into said wiring slots by said clamping mechanism; wherein said clamping mechanism is a clamping mechanism common to each of said production lines and is used to perform S4 and S6 for each of said production lines. S1: selecting a plurality of said insulating sleeves matched with a size of wiring slots of said flat wire motor stator, and pre-processing the insulating sleeves to a length by cutting according to a size of the flat wire motor stator; S2: fixing the flat wire motor stator into a positioning plate set of a production line among two or more production lines; S3: placing the pre-processed insulating sleeves into a feed mechanism of said production line, and conveying the pre-processed insulating sleeves through a conveying mechanism of said production line to a positioning mechanism of said production line, said positioning mechanism located behind the conveying mechanism; S4: clamping and transmitting, by a clamping mechanism, the insulating sleeves from said positioning mechanism to a position above the wiring slots of the flat wire motor stator; S5: moving a guide plate of a guide mechanism of said production line to a position above the flat wire motor stator in the positioning plate set, wherein S5 is synchronized with S4; S6: inserting the insulating sleeves into the wiring slots of the flat wire motor stator through said guide plate; S7: fully inserting the insulating sleeves into the wiring slots of the flat wire motor stator by a leveling mechanism; and S8: removing the flat wire motor stator, and putting in another flat wire motor stator; resetting these mechanisms, and repeating S1 to S7; wherein each of said production line runs steps S1 to S8, wherein in step S6 said insulating sleeves are inserted into said wiring slots by said clamping mechanism; wherein said clamping mechanism is a clamping mechanism common to each of said production lines and is used to perform S4 and S6 for each of said production lines.