The invention discloses a cantilever part applied to a head gimbal assembly. The cantilever part comprises a flexible part and multiple flexible circuits, wherein the flexible part comprises a grounded conductive substrate and a dielectric layer formed on the conductive substrate; and the flexible circuits are formed on the dielectric layer and extend to the tail part from the front part of the flexible part, the flexible circuit at least comprises a pair of reading lines, at least one through hole is formed at a predetermined position on the reading line to electrically connect the reading line on the conductive substrate, and the conductive substrate layer is partially etched. ESD (electrostatic discharge) damage at each stage of the hard disk drive manufacturing process can be reduced, the manufacturing cost is reduced, and electric performance of the cantilever part interconnection is improved.