The invention provides a soil release agent and a detergent composition blended therewith. The invention relates to a crosslinked product obtained by reacting a compound having 2 to 32 hydroxyl groups, such as triethanol amine, with a compound having at least two functional groups reacting with hydroxyl groups, such as (poly)ethylene glycol diglycidyl ether, a soil release agent containing the crosslinked product, and a detergent composition containing the soil release agent.