A slide gate damper system comprises (a) a duct frame adapted for mounting in a duct, (b) a gate support frame mounted outside the duct in association with the duct frame; (c) guide rails positioned on the frame members of the gate support frame, (d) a slide gate positioned within the gate support frame, (e) a power source mounted on the slide gate and movable therewith and (f) a drive mechanism operatively connecting the power source to the gate support frame. Mounting of the power source on the slide gate and adapting the drive mechanism accordingly results in a slide gate damper system with reduced overall weight and support structure.