<p>[PROBLEMS] To provide a guide device enabling a standard slide cover divided into split bodies and accurately positioned to be fixedly mounted at the axial both ends of a moving block body and preventing its displacement from occurring in use. [MEANS FOR SOLVING PROBLEMS] This guide device comprises a moving block assembled in a track rail movably relative to each other. The moving block body is formed in such a shape and a size that its cross section orthogonal to the axial direction can be assembled in the track rail at the intermediate position of the track rail. The side cover (24) is formed of the split bodies (24-1) and (24-2) laterally divided in the right and left directions. A projected pin (26) for positioning is installed on the divided surface of one split body (24-1) and a hole (27) for positioning into which the pin for positioning is fitted is formed in the divided surface of the other split body (24-2). The pin for positioning is fitted into the hole for positioning to form a side cover assembly, and the side cover assembly is fixedly mounted at both ends of the moving block body in the relative moving direction with fixing screws (28-1) and (28-2) passed through fixing screw holes formed in the split bodies (24-1) and (24-2).</p>
