A logistics cargo container locking device comprises a logistics carriage and a cargo container; guiding convex strips extending forwards and backwards are symmetrically arranged on the two side walls of the logistics carriage; racks are arranged on the lower end surfaces of the guiding convex strips; guiding slide grooves extending forwards and backwards and matched with the guiding convex strips are symmetrically formed in the two side walls of the cargo container; locking teeth which can be engaged with the racks are arranged on the bottom walls of the guiding slide grooves; a sliding groove is formed in the bottom wall of the logistics carriage; a sliding lifting top plate can be mounted in the sliding groove in an up-and-down sliding manner; wedge-shaped convex blocks are arranged on the lower end wall of the sliding lifting top plate in a forward-backward symmetric manner; guiding slide rails extending forwards and backwards are arranged in the bottom wall of the sliding groove in a forward-backward symmetric manner; wedge-shaped slide blocks can be mounted in the guiding slide rails in a forward-backward sliding manner; and the extruding inclined surfaces of the wedge-shaped slide blocks are propped against the wedge-shaped surfaces of the wedge-shaped convex blocks. The logistics cargo container locking device has the advantages that the logistics cargo container locking device is simply structured and convenient to use, the operation of the logistics cargo container locking device is stable, and safety accidents in transit can be greatly reduced.