A positioning structure is applied to a male end connector and a female end connector. The female end connector has an inserting slot and two guiding slots. The positioning structure has a case, two guiding pins, two elastic parts, and a positioning member. The two guiding pins are connected to the case. The male end connector is located between the two guiding pins. The elastic parts are connected to the case and to the male end connector. The positioning member has a first positioning hole and two second positioning holes. The first positioning hole is used for the male end connector passing through to enter the inserting slot. The second positioning holes are used for the guiding pin passing through to enter the guiding slot.