The invention provides aqueous coating agent composition, a coating film and a coating product. The aqueous coating agent composition can form a coating film having appearance maintenance and stain resistance for long term at high level; the aqueous coating agent composition has dispersoid (CD) of a copolymer (C) and inorganic oxide (D); the copolymer (C) comprises a structure unit (A) and a structure unit (B); the structure unit (A) is silane (a) having a specific structure; the structure unit (B) is silane (b) having a specific structure; the content of the structure unit (A) in the copolymer (C) takes up of 32 to 70% by weight according to hydrolytic condensation conversion; and the content of the structure unit (B) in the copolymer (C) takes up of 23 to 45% by weight according to hydrolytic condensation conversion.