A linear guide apparatus comprising: a guide rail; a slider; and a plurality of rolling elements, the guide rail and the slider being disposed so as to face with each other and including therebetween a rolling surface which forms a rolling channel for the rolling elements, the rolling elements being configured to roll over the rolling channel to allow either one of the guide rail and the slider to take a linear motion with respect to each other, a plurality of side seals (4,5) each of which contacts the guide rail in a sliding manner, being disposed at each of both ends in a direction in which the slider moves, characterised in that the plurality of side seals each comprise a metal plate, and a tabular member and a lip both formed of an elastic material, the metal plate, the tabular member, and the lip being integral with each other, an inner seal among the plurality of side seals is individually attached to the slider by a first screw engaging with the slider, the inner seal being disposed at an innermost side of the direction in which the slider moves, an outer seal among the plurality of side seals is individually attached to the slider by a second screw other than the first screw, the second screw engaging with the slider, the outer seal being disposed at an outermost side of the direction in which the slider moves, a first through-hole that allows an axis of the first screw to pass through, and a second through-hole that allows an axis of the second screw to pass through are formed in the metal plate of the inner seal and the tabular member thereof, the outer seal comprises a third through-hole that allows a head of the first screw to be revealed, and a fourth through-hole that is communicated with the second through-hole of the inner seal, and a spacer is disposed in the second through-hole of the metal plate of the inner seal and the tabular member thereof, an end face of the spacer contacts an end face of the slider, an another end face of the spacer contacts a periphery of the fourth through-hole of the metal plate of the outer seal, and the axis of the second screw is fitted in the spacer with play, a guide rail; a slider; and a plurality of rolling elements, the guide rail and the slider being disposed so as to face with each other and including therebetween a rolling surface which forms a rolling channel for the rolling elements, the rolling elements being configured to roll over the rolling channel to allow either one of the guide rail and the slider to take a linear motion with respect to each other, a plurality of side seals (4,5) each of which contacts the guide rail in a sliding manner, being disposed at each of both ends in a direction in which the slider moves, characterised in that the plurality of side seals each comprise a metal plate, and a tabular member and a lip both formed of an elastic material, the metal plate, the tabular member, and the lip being integral with each other, an inner seal among the plurality of side seals is individually attached to the slider by a first screw engaging with the slider, the inner seal being disposed at an innermost side of the direction in which the slider moves, an outer seal among the plurality of side seals is individually attached to the slider by a second screw other than the first screw, the second screw engaging with the slider, the outer seal being disposed at an outermost side of the direction in which the slider moves, a first through-hole that allows an axis of the first screw to pass through, and a second through-hole that allows an axis of the second screw to pass through are formed in the metal plate of the inner seal and the tabular member thereof, the outer seal comprises a third through-hole that allows a head of the first screw to be revealed, and a fourth through-hole that is communicated with the second through-hole of the inner seal, and a spacer is disposed in the second through-hole of the metal plate of the inner seal and the tabular member thereof, an end face of the spacer contacts an end face of the slider, an another end face of the spacer contacts a periphery of the fourth through-hole of the metal plate of the outer seal, and the axis of the second screw is fitted in the spacer with play,