Organic aerosols will likely form in semisolid, glassy, and high viscous state in the atmosphere, which show nonequilibrium kinetic characteristics at low relative humidity (RH) conditions. In this study, we applied optical tweezers to investigate the water transport in a sucrose/(NH4)(2)SO4 droplet with high organic to inorganic mole ratio (OIR). The characteristic time ratio between the droplet radius and the RH was used to describe the water mass transfer difference dependent on RH. For OIR greater than 1:1 in sucrose/(NH4)(2)SO4 droplets, the characteristic time ratio at low RH (