The invention relates to an aqueous paint, and specifically relates to an aqueous hammer paint, and belongs to the technical field of chemical industry. An aqueous acrylic acid modified epoxy emulsion is used as a film forming substance; acrylic acid monomer and epoxy resin conduct a grafting copolymerization reaction to introduce strong hydrophilic group -COOH into the epoxy resin and carry out water-borne modification on the resin; the prepared emulsion particle is fine (reaching nanometer level) and stable. Acrylic acid resin has excellent gloss retention, colour retention and ultraviolet resistance; and epoxy resin has excellent alkali resistance, chemicals resistance solvent resistance and extraordinary adhesive force; therefore the paint film has excellent comprehensive performances.