AIM: To investigate the relevance of formation of fibrovascularization between vascular endothelial growth factor (VEGF) and hydroxyapatite(HA) orbital implants; and the mechanism of dexamethasone suppression on fibrovascularization of HA implants. METHODS: Twenty rabbits were randomly divided into experimental group and control group with 10 in each; each group were used HA implants implanted in rabbit eyes and tobramycine eyedrop was used 4 times per day postoperatively. Peribulbar injection of dexamethasone 0.5mg was applied in the experimental group every other day 48 hours after operation to the end of the experiment, and the growth state of conjunctiva in both groups were observed. 2 HA implants from experimental group and control group respectively were extracted for testing the positive expression of VEGF by immunohistochemistry 3,7,14,21,28 days after operation. RESULTS: There was a significant correlation between HA implants fibrovascularization and the expression of VEGF. Histological examination confirmed that after 14 days, the experimental group HA significantly reduced inflammatory cell infiltration, immunohistochemistry showed that VEGF expression in the experimental group was significantly lower than that in the control group. CONCLUSION: It is closely related between HA implant fibrovascularization and inflammatory reaction; VEGF may be involved in the formation of fibrovascularization, dexamethasone may be through inhibiting the inflamma-tory response and VEGF expression, and thus inhibit implants of fibrovascular growth.