Provided is a sliding door device which can move a support shaft attached to a sliding door along an inclined portion of a rail by using a pull-in device. The rail (6a) is provided with the straight portion (11) for linearly guiding the support shaft attached to the sliding door (2) and the inclined portion (12) which is inclined with respect to the straight portion (11) and obliquely guides the support shaft. The straight portion (11) of the rail (6a) is provided with the pull-in device (15) which can capture a trigger (18) provided on the straight portion (11) of the rail (6a) and linearly move along the straight portion (11) of the rail (6a) when the sliding door (2) is closed. A pull-in force transmission part (20) for moving the support shaft along the inclined portion (12) of the rail (6a) is coupled to the pull-in device (15).