Objective:To compare the effect of topical application of hydroxycamptothecin(HCPT) and mitomycin C(MMC) in preventing postlaminectomy epidural adhesion. Methods:Laminectomies were performed at L1 on 30 rats. Cotton pads soaked with 0.1 g/L HCPT, 0.1 g/L MMC or saline were applied to the operative sites for 5 min. Somatosensory evoked potential(SEP) was detected before or after administration. The effects of epidural adhesion after 4 weeks were observed with macroscopic observation,histopathological evaluation and MRI scanning. The count of fibroblasts and the area of epidural scar tissue were calculated. Results:Moderate to marked epidural adhesion was found in HCPT group,no obvious adhesion was formed in MMC group,while severe epidural adhesion formed in control group. SEP has no significant difference before and after administration. The count of fibroblasts and the area of epidural scar in HCPT and MMC group was obviously less than that in control group. Conclusion:Topical and transitory application of MMC and HCPT may be a successful method of preventing postlaminectomy epidural fibrosis.