A display illumination structure comprising: a display including a gauge portion being backlit; a light source which is disposed on a back surface side of the display; a light guiding member configured to guide light emanating from the light source to at least a back surface side of the gauge portion, the light guiding member including: an incident portion on which the light emanating from the light source is incident; a horizontally extending portion configured to guide the light emanating from the light source along the gauge portion; and an interior reflecting bent portion configured to reflect the light that enters from the incident portion towards the horizontally extending portion; and a housing on a front surface side of which the display is provided, in an interior of which the light source and the light guiding member are disposed, the housing including: a main reflecting surface, provided on an inner surface of the housing, configured to reflect light that exits from the light guiding member so as to be returned to the light guiding member; and an auxiliary reflecting surface, provided on the inner surface of the housing in a position which lies closer to the light source, configured to reflect light that is not incident on the incident portion and light that leaks from a halfway portion of the light guiding member towards a low-luminance poorly illuminated portion, the low-luminance poorly illuminated portion being formed in a position on the gauge portion which is closer to the light source, wherein the auxiliary reflecting surface is provided on a back side of the low-luminance poorly illuminated portion; and the auxiliary reflecting surface includes a concavely recessed light collecting portion configured to collect light towards the low-luminance portion. a display including a gauge portion being backlit; a light source which is disposed on a back surface side of the display; a light guiding member configured to guide light emanating from the light source to at least a back surface side of the gauge portion, the light guiding member including: an incident portion on which the light emanating from the light source is incident; a horizontally extending portion configured to guide the light emanating from the light source along the gauge portion; and an interior reflecting bent portion configured to reflect the light that enters from the incident portion towards the horizontally extending portion; and an incident portion on which the light emanating from the light source is incident; a horizontally extending portion configured to guide the light emanating from the light source along the gauge portion; and an interior reflecting bent portion configured to reflect the light that enters from the incident portion towards the horizontally extending portion; and a housing on a front surface side of which the display is provided, in an interior of which the light source and the light guiding member are disposed, the housing including: a main reflecting surface, provided on an inner surface of the housing, configured to reflect light that exits from the light guiding member so as to be returned to the light guiding member; and an auxiliary reflecting surface, provided on the inner surface of the housing in a position which lies closer to the light source, configured to reflect light that is not incident on the incident portion and light that leaks from a halfway portion of the light guiding member towards a low-luminance poorly illuminated portion, the low-luminance poorly illuminated portion being formed in a position on the gauge portion which is closer to the light source, wherein a main reflecting surface, provided on an inner surface of the housing, configured to reflect light that exits from the light guiding member so as to be returned to the light guiding member; and an auxiliary reflecting surface, provided on the inner surface of the housing in a position which lies closer to the light source, configured to reflect light that is not incident on the incident portion and light that leaks from a halfway portion of the light guiding member towards a low-luminance poorly illuminated portion, the low-luminance poorly illuminated portion being formed in a position on the gauge portion which is closer to the light source, wherein the auxiliary reflecting surface is provided on a back side of the low-luminance poorly illuminated portion; and the auxiliary reflecting surface includes a concavely recessed light collecting portion configured to collect light towards the low-luminance portion.