To investigate the effect of basic Fibroblast Growth Factor (bFGF) on fibrovascular ingrowth into porous polyethylene orbital implants (Medpor) and to investigate any differences according to the method of administration. For the treated groups, after evisceration and Medpor implantation, bFGF was administered by soaking Medpor in the bFGF solution, and/or by injecting bFGF into the Medpor 1 week after the operation. Implants were removed 4 weeks after the operation and examined for the degrees of fibrovascular ingrowth by light microscopy. The percentages of the cross-sectional area of the implant occupied by fibrovascular ingrowth and the numbers of proliferated vessels were significantly higher in the bFGF-treated groups (Mann Whitney test, p<0.05). Administration routes had no effect on the degree of fibrovascular ingrowth (Kruskal-Wallis test, p>0.05). bFGF promoted fibrovascular ingrowth into porous polyethylene orbital implants regardless of the route of administration. Therefore, bFGF might be helpful to prevent complications such as implant exposure.