A dock slider, comprising: a guide column; wherein an upper wing plate and a lower wing plate are connected by the guide column; the guide column is provided on a front end side of the slider; a space formed between the upper wing plate and the lower wing plate forms a sliding groove; an upper guide plate is downwardly and vertically provided from a left edge and a right edge of the upper wing plate, respectively; the upper guide plate is configured to limit a sliding direction of the slider; a lower guide plate is upwardly and vertically provided from a left edge and a right edge of the lower wing plate, respectively; the lower guide plate is configured to limit the sliding direction of the slider and arranged corresponding to the upper guide plate; the upper wing plate and the lower wing plate are respectively provided with an upper limit portion and a lower limit portion at sites adjacent to a rear end side of the slider; the space surrounded by the upper limit portion and the lower limit portion forms a limit cavity configured to accommodate the rear end side of the slider; a cross-sectional area of the limit cavity is larger than a cross-sectional area of the sliding groove at the rear end side of the slider; wherein the upper limit portion comprises two upper clasping bodies symmetrically arranged with respect to a center line of the upper wing plate, and the lower limit portion comprises two lower clasping bodies symmetrically arranged with respect to a center line of the lower wing plate; the limit cavity formed by the two upper clasping bodies and the two lower clasping bodies is rectangular and configured to limit a lateral movement of the rear end side of the slider; characterized in that an upper sliding strip is provided on an inner side of the upper guide plate along the sliding direction of the slider; the upper sliding strip is connected to both the upper guide plate and the upper wing plate; an end of the upper sliding strip is gradually contracted toward the rear end side 42) of the slider to form an upper sliding inner arc surface; and a lower sliding strip is provided on an inner side of the lower guide plate along the sliding direction of the slider; the lower sliding strip is connected to both the lower guide plate and the lower wing plate); an end of the lower sliding strip is gradually contracted toward the rear end side of the slider to form a lower sliding inner arc surface. wherein the upper limit portion comprises two upper clasping bodies symmetrically arranged with respect to a center line of the upper wing plate, and the lower limit portion comprises two lower clasping bodies symmetrically arranged with respect to a center line of the lower wing plate; the limit cavity formed by the two upper clasping bodies and the two lower clasping bodies is rectangular and configured to limit a lateral movement of the rear end side of the slider; characterized in that an upper sliding strip is provided on an inner side of the upper guide plate along the sliding direction of the slider; the upper sliding strip is connected to both the upper guide plate and the upper wing plate; an end of the upper sliding strip is gradually contracted toward the rear end side 42) of the slider to form an upper sliding inner arc surface; and a lower sliding strip is provided on an inner side of the lower guide plate along the sliding direction of the slider; the lower sliding strip is connected to both the lower guide plate and the lower wing plate); an end of the lower sliding strip is gradually contracted toward the rear end side of the slider to form a lower sliding inner arc surface.