A sliding roof device is made up of a pair of laterally spaced guide rails provided at inner peripheries of an open area formed in a vehicular roof panel, the guide rails supporting a movable panel in movable fashion in order to open and close the open area; a front frame connecting a front end of one of the guide rails and a front end of the other, the front frame and the pair of the guide rails constituting a sunroof frame; and a driving mechanism including a motor, a gear mechanism driven by the motor, an output gear associated with the gear mechanism, a geared cable engaged with the output gear in meshing fashion and connected to the movable panel for the movement thereof when the motor is turned on, and a casing pipe through which the geared cable is passed in movable fashion, characterized in that a housing and a box are provided, the housing placing the output gear outside the sunroof frame, the housing accommodating therein the gear mechanism, the box being formed integrally with the sunroof frame, the box covering the meshing engagement between the geared cable and the output gear.