SLIDING DOOR DEVICE FOR VEHICLE

A sliding door device for a vehicle includes a door configured to open or close a door opening formed in a vehicle body, a door arm including one end portion rotatably connected to the door and the other end portion provided to be movable along a side sill of the vehicle body, a mover connected to the other end portion of the door arm and configured for straight line movement along the side sill of the vehicle body, a door arm plate configured to rotatably connect the mover with the other end portion of the door arm and provided to perform cycloid rotation and straight line movement when the mover moves along the side sill, a pin provided to protrude on the door arm plate, and a cycloid rail provided in the side sill and configured to provide a path on which the roller moves when the other end portion of the door arm moves along the side sill.