The invention relates to the technical field of handset accessories, and particularly relates to the design of a plug for a handset audio interface, which comprises a first electrode, a second electrode, a third electrode, a fourth electrode, a first insulating layer, a second insulating layer and a third insulating layer. The first electrode, the second electrode, the third electrode and the fourth electrode are exposed to the surface of a plug body from the top end to the tail end of the plug body in sequence. The tail end of the second electrode, the tail end of the third electrode and one part of the first electrode are retracted into the fourth electrode. On the original basis in the prior art, the length of the tail end of the plug is greatly shortened. Meanwhile, the fourth electrode also protects the tail ends of other electrodes. It is well known that, the longer the length of an object, the easier the object to bend. In this way, the tail end of a conventional plug of an original structure is feathering out from being coarse, so that the conventional plug is easier to break during usage. Therefore, the service life of the conventional plug is heavily influenced. According to the technical scheme of the invention, the length of the above plug is obviously shortened by 810 mm at the most compared with common electronic accessory plugs. Therefore, the plug is more convenient to use. At the same time, the plug is not easy to damage, so that the service life of the plug is effectively prolonged.