In a surface light source device of side light type and a display employing the same, illumination light of high grade is allowed to emit by reducing irregularities in luminance caused along a muntin of a support member to support components such as a light guide plate 2 and a reflection sheet 21. A light quantity correction surface 21A is formed between the reflection member 21 and a support member 11. Otherwise, a member providing the light quantity correction surface is arranged on the rear of the support member. A quantity of illumination light in a portion of a muntin 11B of the support member 11 is made approximately equal to that in a portion of an aperture 11C, and the irregularities in luminance caused correspondingly to the muntin are reduced. The light quantity correction surface may be provided by a surface of the muntin itself or ink coated on the muntin by means of printing. Further, a member providing the light quantity correction surface may be arranged between the muntin and the reflection member 21. This member may be an additional reflection sheet.