To provide a manufacturing method which makes it possible to directly disperse a polyester resin into an aqueous dispersion medium without using an organic solvent and which thereby can give a water dispersion composition of the polyester resin which contains the polyester resin particles small in particle sizes and almost spherical and is excellent in standing stability.

The manufacturing method of the aqueous dispersion composition of the polyester resin comprises the step of emulsifying/dispersing the polyester resin and a surfactant into the aqueous dispersion medium. The surfactant is a compound represented by general formula [3], wherein R3 is a 3-6C alkylene group; R4 is a residue formed by eliminating active hydrogens from a diol having total carbon atoms of 4 or more; h is a positive integer to make 50-4,000 in a total in the molecule; and k is 0 or a positive integer to make 0-100 in a total in the molecule. The surfactant has a mean HLB value of ≥15 and is used so that its total mass may be 2-50 parts by mass based on 100 parts by mass of the polyester resin.