To provide a process for efficiently producing a fluorine type antifouling composition employing a short chain Rf group, which can be made in the form of an aqueous dispersion containing substantially no volatile organic solvent and has a good soil release property (SR property).A process for producing an antifouling composition, which comprises a step of subjecting monomer components (Z) comprising from 30 to 80 mass % of a monomer (a) having a polyfluoroalkyl group in which the number of carbon atoms to which fluorine atoms are bonded is from 4 to 6, and from 20 to 70 mass % of a monomer (b) having no polyfluoroalkyl group and having a hydrophilic group, to solution polymerization in a volatile organic solvent having a boiling point of at most 100° C. in the presence of a surfactant (c) comprising an ethylene oxide adduct of 2,4,7,9-tetramethyl-5-decyne-4,7-diol to form a fluorocopolymer (A), and a step of volatilizing the volatile organic solvent after the solution polymerization and adding an aqueous medium to form an aqueous dispersion.