This paper reports an experimental work on the measurement of effective electrical conductivity of aqueous suspensions of aluminum oxide nanoparticles (nanofluids). Experiments were performed both as a function of volume fraction and temperature to examine the effects of their variations on the electrical conductivity of alumina nanofluids. The results indicate considerable enhancement of electrical conductivity with both increase in volume fraction and temperature. However, the dependence of the effective electrical conductivity on temperature is much less than the volume fraction. (C) 2009 Elsevier B.V. All rights reserved.