This paper deals with the determination of thermal conductivity of water based TiO₂ nanofluids as a function of temperature in the range of 30°C to 70°C with different volume concentration of TiO₂ nanoparticles. In the present experimental investigation, nanofluids are prepared with TiO₂ nanoparticles of average size of 21 nm and measurements are made using test setup, specifically designed by namely PA Hilton, UK [17]. Nanofluids with different volume concentrations in the range of 0.2% to 1.0 % (by weight) of TiO₂ are used. Based on the experimental results it is found that the thermal conductivity of nanofluids increases with the percentage of volume concentration and temperature. Experimental results are compared with the models available in the open literature. The experimental results of thermal conductivity of nanofluids of the present investigation closely compare with the predictions of the model proposed by Murshed et al [8]. All other models have under-predicted the thermal conductivity of TiO₂ nanofluids by as much as 20 to 40%. The experimental results in the present investigations are highly encouraging in terms of enhancement of thermal conductivity.