Ocular components were measured by keratometry, phakometry, and ultrasonography on 176 young adults. Refractive error was measured by retinoscopy. Mean vitreous depth was greater and the cornea was steeper in myopes than in emmetropes. There were no significant differences between myopes and emmetropes in mean anterior chamber depth, crystalline lens thickness, anterior crystalline lens radius, posterior crystalline lens radius, or crystalline lens power. Coefficients of correlation were calculated for each of the ocular components with refractive error for the entire group of 176 subjects. The components that showed statistically significant correlations with refractive error were vitreous depth and anterior corneal radius. Eyes with greater vitreous depths tended to have flatter anterior corneal surfaces. The slope of the principal axis relating these two variables was significantly different in emmetropes and myopes. Eyes with greater vitreous depths tended to have lesser crystalline lens power. Vitreous depth showed a statistically significant correlation with posterior lens radius, but not with anterior lens radius.