Abstract: A crosslinkable UV absorbing agent prepared by the following steps: (1) preparing a mixture of reactants comprising a UV absorbing compound (A) with multiple pendant hydroxyl groups and an unsaturated monoglycidyl compound (B) with both reactive glycidyl and vinyl groups; (2) mixing a base catalyst (C) with the mixture of reactants; (3) initiating a synthesis reaction of the crosslinkable UV absorbing agent under heating; and (4) recovering the resulting product after the synthesis reaction is completed. The crosslinkable UV absorbing agent is directly applicable in the lens formulation to replace conventional crosslinking agent and UV absorber used in the production of the soft contact lens without any purification or modification.