Visual function improving agents containing compounds having an Rho kinaseinhibitory activity, in particular (R)-(+)-N-(1H-pyrrolo[2,3-b]pyridin-4-yl)-4-(1-aminoethyl)benzamide, as the active ingredient. Because of having effectsof promoting axon extension in retinal gangliocytes and promoting regenerationof optic nerve cells, these agents are useful in treating visual functionerrors in association with various eye diseases caused by damage, defect,degeneration, etc. in retina and optic nerve.