Provided is a vehicular roof structure, which can adjust the quantity of daylighting and which can be set to give a sense of spaciousness to a passenger in the rear seat by the wide field of view from the vehicular upper side while blocking the incident light upon the front seat side. Three louvers are enabled to change their angles of inclination with respect to the longitudinal direction of the vehicle. If the individual louvers arranged at the blocking positions are oriented to slope in a slightly downward direction of the vehicle toward the rear side thereof, a passenger in a rear seat can see, while an incident light to the front seat side is being blocked by the three louvers, the outside of the upper side of the vehicle through the three inclined louvers.