The general field of the invention is that of systems for the optical detection of the orientation and the position of a mobile object in space. The system comprises a fixed electro-optical device comprising a transmission point source, image analysis means and an optical cube corner disposed on the mobile object. The input surface of the cube corner comprises a polygonal-shaped mask, the sides of which comprise a geometric marking to identify them. The fixed electro-optical device comprises photosensitive means close to the point source and disposed in two different recording planes and recording two luminous shapes in perspective of the mask obtained by reflection on the surfaces of the cube corner. The image analysis means comprise means for determining the vanishing points of the two luminous shapes in the two recording planes, the knowledge of the four vanishing points enabling the determination of the position and orientation of the optical cube corner in relation to the fixed electro-optical device.