Light penetration depth in highly scattering tissues can be increased by using hyperosmotic chemical agents such as glycerol, PEG (polyethylene glycol) and glucose. Previous many studies used OCT, spectrometer, integrating method to quantitatively evaluate the optical clearing effect of skin. In this study, we show the optical clearing effect of skin using glycerol and suggest a new quantitative analysis method to evaluate the spatial optical clearing effect of skin using glycerol.