Nonionic surfactant solution is often used to separate and purify biomaterials, and the viscosity of nonionic surfactant solution plays an essential role in the design of separation process. In this study, the viscosity data are obtained for aqueous Triton X-114 ((1,1,3,3-tetramethylbutyl)phenyl polyethylene glycol) solutions of three mass fractions of 0.01, 0.02, and 0.05 at temperatures from 293.15 to 313.15 K, and an empirical correlation describing the effect of temperature on the viscosity is derived. The predicted values by the correlation are in good agreement with the experimental data.