A functional composite film includes one or more combinations of an inorganic layer and an organic layer as underlying base of the inorganic layer on a support, and having the outermost surface with an organic layer thereon, where the organic layer on the outermost surface is formed using an ultraviolet-curable urethane polymer having a weight-average molecular weight of 5,000 to 30,000 and a double bond equivalent of 300 g/mol or more, which has a urethane polymer as the main chain and a side chain having a (meth)acryloyl group at a terminal; a curable urethane polyester; and at least one phosphoric acid compound containing two or less (meth)acryloyl groups and/or a silane coupling agent containing one (meth)acryloyl group, and a quantum dot film using the same. High adhesiveness is obtained between the organic layer and the inorganic layer, and when a quantum dot layer or the like is laminated thereon.