The present invention relates to preparation and application of a temperature-sensitive polyethylene glycol/polyester block copolymer having a bioactive functional group introduced into a side chain thereof. More specifically, it relates to a temperature-sensitive polyethylene glycol/polyester block copolymer including a lactide segment having a bioactive functional group introduced into a side chain thereof and a method for preparing same. The temperature-sensitive polyethylene glycol/polyester block copolymer according to the present invention having a bioactive functional group introduced into a side chain thereof can be widely used as a drug delivery system, a support for tissue engineering, an adhesion inhibitor, etc.
