The present invention estimates with greater accuracy the growth state of plants. A growth state estimation device which comprises: a division means which divides a photographic image of a plant into a plurality of division regions on the basis of growth characteristics of the plant a calculation means which, with respect to each of the plurality of division regions divided by the division means, calculates statistics of division image data of each division region, said division image data comprising images of the division regions and an estimation means which estimates the growth state of the plant on the basis of the statistics calculated by the calculation means.
