AIM: To develop a 5-fluorouracil (5-FU) mesoporous poly(lactic) acid (PLA) delivery system for glaucoma filtration surgery suitable for a single subconjunctival implantation. METHODS: The 5-FU was infiltration-loaded into mesoporous PLA. In vitro and in vivo release experiments and ocular toxicology evaluation of the formulation were performed. The antiproliferative effect of this 5-FU-PLA tablet after glaucoma filtration surgery in rabbits was evaluated. Pathology, immunohistochemistry, and Western blot were used to further validate the inhibitory effect of this sustained release system. RESULTS: Various drug formulations were tested, and two 5-FU-PLA tablets, namely 1.5P15 (5-FU 1.5 mg+PLA 15 000 Da) and 2.5P15 (5-FU 2.5 mg+PLA 15 000 Da), had the most suitable release profiles in vitro. Further in vivo studies confirmed the safety and sustained-release profiles of both drugs. Both 5-FU-PLA tablets, relative to the free drugs, significantly inhibited tissue proliferation after glaucoma filtration and improved surgical success. Western blot showed that transforming growth factor-β (TGF-β) and connective tissue growth factor (CTGF) were inhibited by 5-FU after filtration surgery, with the effects of the 5-FU-PLA tablets being more lasting. CONCLUSION: The tested 5-FU-PLA tablets provide a sustained release of 5-FU, which may be used for a single subconjunctival implantation to inhibit proliferation after filtration surgery.