Prism Gauges is an indicator gauge that has a flat light conducting prism with an upper beveled surface positioned between the translucent dial and movement of the indicator. The prism receives light from a source located in the rear portion of the gauge and laterally of said movement, such that light is reflected downwardly by the beveled edge through the prism to illuminate the dial and pointer. A second annular prism may also be provided with a beveled surface so as to reflect light from the source across the face of the dial.