The utility model relates to a lithium-ion battery locking device, which is used for positioning lithium-ion batteries in a battery transportation process and comprises a rotating spindle supported by a bracket. The lithium-ion battery locking device is characterized in that a plurality of locking stop blocks are arranged on the rotating spindle; the rotating spindle is additionally connected with a transmission device which is formed by connecting a plurality of connecting rods; the lower end of the transmission device is connected with a slide bar; the lower half part of the slide bar passes through a mechanism box supported by the bracket; a slide bar stop sheet used for limiting the lifting height of the slide bar, and a return spring capable of enabling the slide bar to return to the original position are arranged in the mechanism box; a slide block is arranged below the slide bar; and the uppermost end of the slide block can be contacted with the lowermost end of the slide bar. The lithium-ion battery locking device overcomes the defect of complication in locking and unlocking movement in the prior art, and can be used for rapidly positioning the lithium-ion batteries in the battery transportation process, so safe and rapid transportation of the lithium-ion batteries is realized.