An electron source substrate has an electron-emitting device consisting of a pair of device electrodes and an electroconductive thin film having an electron-emitting region; and metal wiring coupled to the device electrodes and made in a composition different from that of the device electrodes, on a substrate. A shortest distance between the conductive thin film and the metal wiring along an interface between the device electrodes and the substrate is not less than 50 μm. This configuration is able to effectively prevent diffusion of the wiring metal to the conductive thin film and to the electron-emitting region which can cause degradation of electron emission characteristics.