The motion guide device includes a lubricant supply passage provided in at least one of a pair of cover members provided to a movable member and configured to supply lubricant to an endless circulation passage, in which the lubricant supply passage includes at least a first lubricant supply passage formed to extend in a direction orthogonal to a longitudinal direction of the track member from at least one of a left side surface and a right side surface of the cover member, and a second lubricant supply passage connected to the first lubricant supply passage , and a passage shape in a place connected to the first lubricant supply passage of the second lubricant supply passage is configured as a diameter-expanded hollow section having a diameter more expanded than a passage shape of another place. Thus, a new form of a cover member is provided.

The motion guide device includes a lubricant supply passage provided in at least one of a pair of cover members provided to a movable member and configured to supply lubricant to an endless circulation passage, in which the lubricant supply passage includes at least a first lubricant supply passage formed to extend in a direction orthogonal to a longitudinal direction of the track member from at least one of a left side surface and a right side surface of the cover member, and a second lubricant supply passage connected to the first lubricant supply passage , and a passage shape in a place connected to the first lubricant supply passage of the second lubricant supply passage is configured as a diameter-expanded hollow section having a diameter more expanded than a passage shape of another place. Thus, a new form of a cover member is provided.

The motion guide device includes a track member in which a rolling member rolling surface is formed along a longitudinal direction thereof, a movable member which is reciprocally movable with a number of rolling members being interposed therebetween and which is provided with a loaded rolling member rolling surface constituting a loaded rolling member rolling path opposing to the rolling member rolling surface and a rolling member return path, and a lid member provided with a pair of direction changing paths for connecting both end portions of the loaded rolling member rolling path and the rolling member return path to thereby constitute an endless circulation path. Flange portions are formed to both end portions of the movable member in the reciprocally moving direction by means of insert molding, and the flange portions are provided with fitting portions formed to end portion sides of the movable member.