PURPOSE: To improve the air-tightness of a sliding door device by fitting a drawing sash-roller provided to a sliding door panel and inclined to a meeting style side against the closing direction to a drawing-groove such as a doorsill to pull the sliding door panel near to the meeting style side before the sliding door panel is closed.

CONSTITUTION: In directly before the closing position of a sliding door panel 4, a travelling sash-roller 11 falls into a recess section 14, and the panel 4 comes down. After that, a drawing sash-roller 12 kept in a state to float for the sash- roller 11 and, at the same time, mounted in a state to incline backward toward the closing direction is fitted in inclined drawing grooves 15 provided to the doorsill, etc. Then, the sash-roller 12 is rolled along the grooves 15, and the panel 4 is pulled near to the slantly backward meeting style side. The meeting style surface of the panel 4 is fixed through an air-tight member and is pushed against the meeting style surface of a panel 3, and a space between the meeting style sections is surely sealed. By the constitution, excellent air-tightness can be ensured, and cost can be reduced.