The invention relates to a key buckle which not only can be used as a key ring, but also can be used for supporting a mobile phone or a tablet personal computer in an inclined state on a table board and a use method of the key buckle. The key buckle comprises a volute spiral spring type main body, wherein a vertical key hanging section is arranged in the middle adjacent to the main body, and the section size of the vertical key hanging section is smaller than that of the other part of the main body. A plurality of chambering blocks for preventing keys arranged on the main body in a penetrating way from sliding out of the outer end of the main body are arranged on the inner side wall of the main body and at the outer end adjacent to the main body. The use method of the key buckle comprises the following steps: obliquely placing the mobile phone or the tablet personal computer on the table board; clamping one end of the mobile phone or one end of the tablet personal computer between the outer end of the main body and the outer side surface of the second circle of the main body and loosening a hand; after the moderate deformation of the main body, supporting the inclined mobile phone or the inclined tablet personal computer.