PURPOSE: To prevent a roller from easily coming off a rail even if a lateral force is applied, in a V-shape sliding-door traveling device, by providing a sloped traveling part of the roller in which both the outer circumferential sides are inclined; and also to prevent occurrence of large sound, and occurrence of slight opening due to repulsion, even if a sliding door is forcibly closed, by weakening moving energy directly before the door is closed.

CONSTITUTION: In the vicinity of a roller 2 whose traveling parts 9, 9 are sloped at both the outer circumferential sides, a guide rod 3 is installed so as to be vertically movable, whose lower end is positioned nearly flush with a lower part of the roller when it is positioned in the uppermost position, and whose lower end is positioned nearly in the bottom of the guide groove 17 in a central part of a rail 14 when it is positioned in the lowermost position. In the end part of the rail, a brake device 18 consisting of two elastic squeezing bodies 19, 19 is installed.