A light absorption coefficient distribution estimation device includes a detection section and a light absorption coefficient distribution estimation section. The detection section detects the received light intensity of scattered light from a subject at a plurality of light-receiving positions that differ in distance from an irradiation position at which measurement light is applied to the subject. The light absorption coefficient distribution estimation section estimates the light absorption coefficient distribution of the subject using the received light intensity, a propagation optical path length model that specifies a propagation optical path length on a basis of the distance, and a first model that specifies the received light intensity on a basis of the distance when absorption of light is at a predetermined value.