The present invention discloses a deflector of a sliding roof system including a blade provided along on an front edge of an opening of a fixed roof and moving upward and downward along with an opening and closing movement of a roof panel; arms installed on right and left end portions of the blade, each of the arms provided with a cam pin and a support pin; a cam groove that guides the cam pin so as to define a movement trajectory of the blade; and a support groove that guides a frontward and backward movement of the support pin, wherein the support groove includes a guide frame that guides a frontward and backward movement of the roof panel.