A surface position detection apparatus capable of highly precisely detecting the surface position of a surface to be detected without substantially being affected by relative positional displacement due to a polarization component occurring in a light flux having passed through a reflective surface. In the apparatus, a projection system has a projection side prism member (7) having first reflective surfaces (7b, 7c), and a light receiving system has a light receiving prism member (8) having second reflective surfaces (8b, 8c) arranged in correspondence with the projection side prism member. The surface position detection apparatus further has a member for compensating relative positional displacement due to a polarization component of a light flux having passed through the first and second reflective surfaces.