A document generation system which generates, from a first document in which a plurality of text groups constituted by a plurality of lines arranged in a first direction is arranged in a second direction different from the first direction, a second document includes: a ranking unit configured to rank each of the plurality of text groups according to an order in which a person reads the first document; and a generating unit configured to generate, as the second document, a document in which each of the plurality of text groups is arranged one by one in the first direction in ascending order ranked by the ranking unit.