A drug-introduced photo-crosslinked hyaluronic acid derived gel which is a photo-crosslinked hyaluronic acid gel into which a drug is introduced through a covalent bond, and has characteristics that are capable of extruding from an injection device. The drug-introduced photo-cross-linked hyaluronic acid derived gel is capable of extruding, for example, by an injection needle of 20 to 25 gauge with a pressure of 0.5 to 5 kg/cm2.