Provided is a photomultiplier tube having a fine structure for achieving a high multiplication efficiency. The photomultiplier tube is provided with an envelop inside of which is kept in a vacuum state, and on a device mounting plane (40a), which is a part of an inner wall plane defining the inner space of the envelop, a photocathode (22) which is of reflective type, an electron multiplication section (31), an anode (32) and a voltage distributing section (311) are arranged. Especially, the electron multiplication section is composed of a plurality of steps of dynodes for performing cascade multiplication of photoelectrons from the photocathode. The voltage distributing section for applying corresponding voltages to the steps of dynodes, respectively, is on the same plane with the electronmultiplication section.