The ion and water transports across charged mosaic membrane were investigated in the presence of nonelectrolyte (sucrose). In addition, according to irreversible thermodynamics, phenomenological equations were developed in the system of KCl-sucrose mixed solution. From the analysis of the volume flux and solute flux based on the developed equations, practical membrane parameters such as sigma and omega were estimated and compared with the simplest system (KCl/water system). As a result, water flows through charged mosaic membrane caused by KCl diffusion, and osmotic flow of water caused by sucrose were additive. On the other hand, in spite of prediction due to theoretical consideration, the effect of sucrose on KCl transport was too small to detect experimentally.