An object of the present disclosure is to provide a surface light source lighting device capable of realizing direction control and a stable operation with respect to vibration or a great temperature change, required for use in a backlight. This surface light source lighting device causes linear light incident from a light source (2a) to be incident to an edge surface (1L) of a light guide plate (1) via a light incidence portion (3a) including a light incidence lens and a louver, and can thus maintain high reliability with respect to vibration or a temperature change in a use environment. In the light guide plate (1), light reflected by a first light guide pattern (4A) provided on a rear surface thereof is reflected by a second light guide pattern (4B) provided on the same rear surface so that an emission direction is set, and thus light is emitted from a front surface of the light guide plate (1) with desired distribution characteristics.