An electric motor, an end cap thereof and a manufacturing method of the end cap are provided. The end cap includes an insulating body and a filter circuit board mounted to the insulating body. The filter circuit board includes at least two power conductors for receiving an external power source, an insulating support frame integral with the at least two power conductors, and at least one filter element. One end of the at least one filter element is connected to a corresponding power conductor, and the other end of the at least one filter element is grounded.