This paper deals with the measurement of quantities of gases such as nitrogen and carbon dioxide that penetrated through a rubber sheet into mineral oil by the means of combination of manometer and laser heterodyne interferometry. With N_2, the saturated solubility into the rubber is about equal to the one into the VG10 mineral oil, and diffusion coefficient is approximately 1/50 times smaller than VG10 mineral oil. The quantities of gas permeability of N_2 and CO_2 through rubber sheet increase with pressure and temperature.