An electron source that can be used stably for a long time even when hexaboride is used, and an electron beam device using the electron source are provided. The invention is directed to an electron source which includes a filament made of a metal, a metal tube that is fixed to the filament and has a plurality of recesses disposed at least in two axial directions so as to surround a central axis at an outer periphery, and a columnar hexaboride tip that emits an electron, is disposed so as to protrude from the inside of the metal tube to a side opposite to the filament, and is in contact with a bottom of each of the plurality of recesses of the metal tube.