A vascular embolization gelling agent for sustained release of drugs for treating tumors having a drug and a drug carrier. The drugs are antitumor drugs. The drug carrier includes poloxamer polymer and polyvinylpyrrolidone or gel made of the combination, and may be purified before use. The drug carrier accounts for 5-65% of the gel. The particle size of the gel is in the range of 10 nm-150 μm. The embolization agent is a liquid gel at normal temperature, to facilitate direct transcatheter injection, and is rapidly solidified to the gel state in body with the increase of the temperature； it is used to encapsulate different drugs on demand, and can achieve dual efficacy of embolization and drug treatment through local sustained release of the drug. The present invention can be used as the embolization agent for endovascular interventional therapy for transcatheter arterial chemoembolization of various benign and malignant tumors.
