The invention discloses a manufacturing method of magnet unit for wireless charging, including the steps: installing multiple magnetic elements onto a first carrier made of non-magnetic material; moving the first carrier into a magnetizing machine to magnetize all the magnetic elements so that each magnetic element becomes a magnet piece, an N-pole and an S-pole are formed on different portions of the same surface of the magnet piece; installing the magnet pieces onto a second carrier made of magnetically permeable material to form a magnet unit, the magnet pieces are defined in an annular array around the central axis of the second carrier installed on a wireless charging base, the magnet unit cooperates with a charging coil of the wireless charging base to charge a wireless headset. The invention simplifies the manufacturing process and ensures the consistency of magnet pieces in the same magnet unit, also improves the manufacturing efficiency.