The surgical microscope comprises a stand, an arm movably attached to said stand for sustaining a microscope body, an electric control equipment divided into a plural number of units removably piled up on said stand and a foot switch unit to be used for executing various types of functions. Accommodated in each unit are a function control means having a single specific function or plural specific functions different from those of the other units and an independent power source means connected to said function control means in a relation of 1:1 or in a different combination. The surgical microscope can be designed compact as a whole, has high operability and assures high security during operation. Should a function be lost due to troubles during operation, the surgical microscope prevents the other functions from being influenced by the troubles and allows to speedily restore the lost function.