Sliding door device

A sliding door device (S) includes a frame case (1) that includes an opening through which an air flow passes, a slide door (2) that is moved relative to the opening to adjust an aperture ratio of the opening, a shaft (5) that is disposed at an upstream side of the slide door when viewed along the flowing direction of the air flow, and moves the slide door, and a windbreak member (6) that blocks a gap between the shaft and the slide door.