To provide an ultraviolet microscope capable of supplying inert gas to a surface of a sample while securing excellent operability.

The microscope 1 which radiates ultraviolet light to the sample 3, so that the optical image of the sample 3 may be observed is equipped with an objective lens 30 for ultraviolet light where a communicating hole 34 along an optical axis L1 is formed and which blows off the inert gas toward the sample 3 from an aperture part 32a, and a fixed part which is fixed to the microscope 1, where a gas channel 23 making a position corresponding to a communicating port 34' communicate with a gas cylinder 53 side when the objective lens 30 for ultraviolet light is attached is formed, and which guides the inert gas supplied from the gas cylinder 53 to the communicating port 34' through the gas channel 23.