A linear guide device has a guide rail 12, a slider body 15, an end cap 16, a large number of rolling bodies 18, and separators 22. The slider body 15 has a slider side rolling body raceway surface opposed to a rail side rolling body raceway surface 13 formed on the guide rail 12. The end cap 16 has a rolling body direction switching path 21 communicating with a rolling body load rolling path 19 formed between both rolling body raceway surfaces of the guide rail 12 and the slider body 15 and also communicating with a rolling body return path 20 formed in a penetrating manner in the slider body 15, along the longitudinal direction of the guide rail 12. In conjunction with relative linear movement of a slider 14 constituted of the slider body 15 and the end cap 16, the rolling bodies 18 roll in the rolling body load rolling path 19, the rolling body return path 20, and a rolling body direction switching path 21. The separators 22 are arranged between every two adjacent rolling bodies 18. The end cap 16 has a throughhole 25 for assembling the rolling bodies 18 and the separators 22 from the outside of the slider 14 into the rolling body return path 19 and also has a cap member 26 removably fitted in the through-hole 25. The cap member 26 forms part of the rolling body direction switching path 21.