A holding apparatus that holds an optical element above a base includes three holding units provided at different positions along an outer periphery of the optical element. Each holding unit includes a first member provided on the optical element, a second member provided on the base, a columnar third member extending in a direction perpendicular to both a tangential direction and a radial direction of the optical element, and a plate-shaped fourth member having a thickness in the radial direction of the optical element. The first member and the second member are connected to each other with the third member and the fourth member disposed therebetween.