Objective To investigate the efficacy of developable iodized oil-fluorouracil polylactic acid microspheres for treatment of New Zealand rabbit liver cancer model. Methods The model rabbits were randomly divided into three groups. The femoral arteries of the right hind limbs were separated, a microcatheter was inserted through the femoral artery to the hepatic artery via a catheter, and the corresponding drugs were injected to the peripheral arteries around the hepatic tumor tissue. The blank control group was not given any medication; the drug control group was given fluorouracil injection and developable iodized oil injection; and the experimental group was given self-made iodized oil-fluorouracil polylactic acid microspheres. Regular imaging was used to observe tumor growth and drug embolism status. Results Developable iodized oil-fluorouracil polylactic acid microspheres effectively achieved embolization around the tumor tissues, resulting in notable tumor cell apoptosis, and the effects were developable and durable. Conclusion Developable iodized oil-fluorouracil polylactic acid microspheres have sustained-release property and can be better developed, showing a promising clinical application future.