The invention relates to a structural element (1) for a fuselage cell structure of an aircraft, in particular a stringer profile (2) or an annular former segment, the structural element (1) being made from a composite material, in particular from a carbon-fibre-reinforced epoxy resin. According to the invention, the structural element (1) comprises at least one positioning aid (10, 11) for facilitating position determination by means of a measuring system. A laser measuring system and/or a tactile measuring system (22) may be used as a measuring system. As a result of the reflector (12) which can be attached to the positioning aid (10, 11) without clearance as a target for the laser measuring system, which is preferably a laser tracker (19), a spatial position of the structural element (1) in relation to a further component (21) can be determined very precisely and without contact. In this case, depending on the distance, measurement accuracies of up to 1/500 mm can be achieved in each direction in space. Following position determination and orientation of the structural element (1), the reflector (12) can be removed from the positioning aid (10, 11). Alternatively, a structural element (1) can be measured by means of measuring arm (23) of the tactile measuring system (23). The positioning aids (10, 11) are then removed from the structural element (1) quickly and without leaving any residue, for example by means of machining methods. Using the structural element (1) according to the invention makes it possible to significantly reduce the production costs involved in the production of complex fibre composite components comprising a plurality of structural elements which are to be positioned precisely in space.