We investigated the proliferation of scleral cells in response to several growth factors in vitro to elucidate the mechanism of scleral growth in visual deprivation myopia. Scleral chondrocytes and scleral fibroblasts were cultured separately in 24-well culture dishes. The number of plated cells was counted after the addition of basic fibroblast growth factor (bFGF), transforming growth factor alpha (TGF-alpha), TGF-beta, insulin-like growth factor I (IGF-I), IGF-II, platelet-derived growth factor AA (PDGF-AA), PDGF-AB and PDGF-BB. All the growth factors studied, except for PDGF-AA, stimulated the proliferation of both scleral chondrocytes and scleral fibroblasts. bFGF showed the highest effect. TGF-beta caused morphologic changes in both scleral chondrocytes and scleral fibroblasts. Various growth factors stimulated the proliferation of scleral chondrocytes and scleral fibroblasts in a similar manner. bFGF was a potent growth stimulator and TGF-beta was suggested to be a growth regulator on scleral chondrocytes and scleral fibroblasts.