A spacer of the present invention for use in an image display device, which has the spacer between a cathode substrate with a cold cathode electron emitting device formed thereon and an anode substrate with a phosphor formed thereon, comprises a phosphate glass having transition metal oxides as its main components, and a higher phosphate concentration layer at the spacer surface. A thickness of the higher phosphate concentration layer is suppressed to 0.5 μm or less. More preferably, the spacer has a water resistant conductive passivation layer formed on its surface. This suppresses the thickness of the higher phosphate concentration layer to a thinner level, so that the spacer is less likely to be charged thus reducing the deflection amount of electron beam. An image display device of the present invention using above spacer can apply a higher voltage to the anode substrate, thus increasing the image quality.