A locking device, comprising a first lock body and a second lock body; the first lock body comprises an angle rotating disc base and an angle rotating disc, wherein the angle rotating disc is connected with the angle rotating disc base, the angle rotating disc can rotate around its own axis; the angle rotating disc base is provided with a first mounting surface for mounting an LED display screen; the second lock body comprises a fixed base and a spring lock, wherein the spring lock is arranged on the fixed base, the fixed base is provided with a limit surface facing one end face of the angle rotating disc and a second mounting surface for mounting another LED display screen; one end face of the angle rotating disc facing the limit surface is provided with a plurality of bevels at intervals along circumferential direction, and included angles of the plurality of bevels and the first mounting surface are different; and the first lock body further comprises a lock plate, the lock plate is arranged between the angle rotating disc base and the angle rotating disc; when the angle rotating disc is rotated, the limit surface fits with different bevels to adjust included angle between the first mounting surface and the second mounting surface, and the spring lock and lock plate are capable to be mutually locked to fix the first lock body and the second lock body temporarily; the angle rotating disc is movably arranged on the angle rotating disc base, and rotating the angle rotating disc can drive the angle rotating disc to move along axial direction of the angle rotating disc relative to the angle rotating disc base; the angle rotating disc base is provided with a thread groove, one end of the angle rotating disc connected with the angle rotating disc base is provided with an external thread, and the thread groove is matched with the external thread to threadedly connect the angle rotating disc base and the angle rotating disc. the lock plate is axially and fixedly connected with the angle rotating disc, so that the lock plate moves along axial direction of the angle rotating disc with the angle rotating disc; and characterized in that the lock plate comprises a lock core and a lock hole arranged on the lock core, the angle rotating disc is provided with an axially penetrating stepped hole, and the lock core is positioned in the stepped hole; the first lock body further comprises a limit screw, and the limit screw is fixed on the angle rotating disc, one end of the limit screw extends into the stepped hole, and the limit screw is used for cooperating with steps of the stepped hole to limit the lock core to move axially relative to the angle rotating disc. the first lock body comprises an angle rotating disc base and an angle rotating disc, wherein the angle rotating disc is connected with the angle rotating disc base, the angle rotating disc can rotate around its own axis; the angle rotating disc base is provided with a first mounting surface for mounting an LED display screen; the second lock body comprises a fixed base and a spring lock, wherein the spring lock is arranged on the fixed base, the fixed base is provided with a limit surface facing one end face of the angle rotating disc and a second mounting surface for mounting another LED display screen; one end face of the angle rotating disc facing the limit surface is provided with a plurality of bevels at intervals along circumferential direction, and included angles of the plurality of bevels and the first mounting surface are different; and the first lock body further comprises a lock plate, the lock plate is arranged between the angle rotating disc base and the angle rotating disc; when the angle rotating disc is rotated, the limit surface fits with different bevels to adjust included angle between the first mounting surface and the second mounting surface, and the spring lock and lock plate are capable to be mutually locked to fix the first lock body and the second lock body temporarily; the angle rotating disc is movably arranged on the angle rotating disc base, and rotating the angle rotating disc can drive the angle rotating disc to move along axial direction of the angle rotating disc relative to the angle rotating disc base; the angle rotating disc base is provided with a thread groove, one end of the angle rotating disc connected with the angle rotating disc base is provided with an external thread, and the thread groove is matched with the external thread to threadedly connect the angle rotating disc base and the angle rotating disc. the lock plate is axially and fixedly connected with the angle rotating disc, so that the lock plate moves along axial direction of the angle rotating disc with the angle rotating disc; and characterized in that the lock plate comprises a lock core and a lock hole arranged on the lock core, the angle rotating disc is provided with an axially penetrating stepped hole, and the lock core is positioned in the stepped hole; the first lock body further comprises a limit screw, and the limit screw is fixed on the angle rotating disc, one end of the limit screw extends into the stepped hole, and the limit screw is used for cooperating with steps of the stepped hole to limit the lock core to move axially relative to the angle rotating disc.