The present invention discloses an aqueous antifogging resin, introducing a molecular segment and a functional group with good hydrophilicity and hygroscopicity, which impart excellent antifogging performance, coating strength and transparent flow appearance to the aqueous antifogging resin and the cured coating has a water contact angle of up to 1˜10°. The present invention further discloses a coating composition including the aqueous antifogging resin, and the cured coating of the coating composition has good antifogging, wear-resistant, water-resistant, chemical resistant, stain-resistant and UV-resistant performance, and excellent adhesion to a substrate; and the coating is firm at the same time, and has excellent film-forming strength and flexual endurance. The coating composition can be used for antifogging surface treatment of the window of mobile phone, PC or PMMA transparent materials, automotive glass and bathroom mirrors and has good long-term stability.