Provided is an electron microscope on which a specimen holder to have high voltage applied is mountable. The specimen holder has safety (electric shock prevention) features, and attention is paid to the specimen holder in terms of operability. The microscope includes a specimen holder having a function of applying a voltage to a specimen mount disposed to load a specimen, a voltage source that supplies the voltage to be applied to the specimen mount, a voltage cable connected at one end thereof to the specimen holder, and a relay unit to which the other end of the voltage cable is connected, the relay unit being placed on a supporting base that supports a lens barrel of the electron microscope.