The present embodiment relates to an electron multiplier having a structure configured to suppress and stabilize a variation of a resistance value in a wider temperature range. In the electron multiplier, a resistance layer sandwiched between a substrate and a secondary electron emitting layer comprised of an insulating material is configured using a single metal layer in which a plurality of metal particles comprised of a metal material whose resistance value has a positive temperature characteristic are two-dimensionally arranged on a layer formation surface, which is coincident with or substantially parallel to a channel formation surface of the substrate, in the state of being adjacent to each other with a part of the first insulating material interposed therebetween.