The present invention provides a crosslinked hyaluronic acid composition including self-crosslinking hyaluronic acid particles having an equilibrium swelling capacity of 3-fold to 10-fold, and an aqueous solvent, wherein a dry weight of the self-crosslinking hyaluronic acid particles based on the total volume of the crosslinked hyaluronic acid composition is 3 w/v% to 8 w/v%. The crosslinked hyaluronic acid composition of the invention uses self-crosslinking hyaluronic acid particles of which the equilibrium swelling capacity is within the above predetermined range. Accordingly, the viscosity does not sharply increase even if the concentration thereof is increased. Therefore, if the crosslinked hyaluronic acid composition is applied to an injection, it is possible to obtain a sufficient curative effect on knee osteoarthritis even with a small frequency of administration.