A microscope support foot (10) includes a central portion (14) and two lateral portions (15, 16), which form receiving chambers (19, 20, 21) by means of separating walls (17, 18) extending as far as a base plate (23). The optical components for an illumination arrangement (28) are disposed in receiving chamber (20) so as to be protected from dust by a seal (25), and the electronic components are disposed in a heat-dissipating manner in the receiving chamber (21), so that the heat-emitting components are in contact with the base plate (23) which is made of heat-dissipating material. This base plate and the lateral portion (16) have ventilation slits (42, 42'). A drive unit (36) for the adjustment of the successviely arranged aperture stop and light field stop (30, 31) is secured in the receiving chamber (19) in such a manner that the adjusting arrangement is accessible from outside and is disposed at a convenient distance from a focussing arrangement (13).