An experimental study is reported of heat transfer to laminar flow of two water-methocel pseudoplastic (power law) solutions in a circular tube subjected to a uniform wall heat flux. The object of this study was to evaluate the effects of non-Newtonian behavior and temperature-dependent consistency on heat transfer. The experimental Nusselt numbers are compared with numerical predictions and experimental data. Two correlations are recommended according to the temperature-dependence of the rheological characteristics.