An aircraft-fuselage structure with an external skin and reinforcement structure, supporting the external skin and includes transverse reinforcement elements and longitudinal reinforcement elements. A door opening is in the external skin, between two transverse reinforcement elements and between two longitudinal reinforcement elements, and a door arrangement is installed therein, the door arrangement having a door frame fastened in the door opening and a door panel fastened on the door frame. The door frame and/or the door panel have/has an outer surface directed towards the surroundings and having a curvature differing from curvature of the external skin adjacent to the door opening, and an adapter arrangement is on the outer surface of the door frame and/or of the door panel and, on a side directed towards the surroundings, has at least one surface element which steadily continues the curvature of the external skin adjacent to the door opening.