To provide a field emission electron source having high reliability while improving emission characteristics, and to provide a light-emitting device using the field emission electron source.

In the light-emitting device 20, the field emission electron source 10, in which electrons passed through an electron passing layer 3 intervened between a lower electrode 2 and a surface electrode 4 are emitted through the surface electrode 4, wherein a film thickness of the lowest section 41 of a first material having good adhesion with the electron passing-through layer 3 and a film thickness of the uppermost section 42 of a second material having a high electron transmission rate are changed continuously or gradually in a mutually reverse direction, is arranged to face a collector electrode 23 and a phosphor layer for emitting fluorescence by excitation light emitted in a light-emitting process of excited Xe gas in an airtight container 21 wherein the Xe gas is enclosed and at least a part of the container 21 is made from a light-transmitting material. The light-emitting device 20 is made to emit light by a control device 25 for controlling voltage applied to the field emission electron source 10 and voltage between the collector electrode 23 and the field emission electron source 10.