The purpose of the current research is to investigate the friction factors for SiO2 and Al2O3 nanoparticles dispersed in ethylene glycol (EG) and water (W) mixtures in 60:40 (60EGW) and 40:60 (40EGW). Apart from the influence of nanoparticles, the thermal conductivity, temperature and viscosity of base fluids also has an impact on the enhancement of thermal conductivity of nanofluids. The trends shown by the nanofluid in enhancing the heat transfer is due to the fact that the nanoparticles present in the base fluid increases the thermal conductivity and the viscosity of the base liquid at the same time. Different solvers and turbulence models are used to try to determine the most accurate CFD method for predicting friction factor in plain tube heat exchanger. Therefore, the enhancement of thermal conductivity leads to increase in the heat transfer performance as well as viscosity of the fluid which in turn results in increase in friction factor. 60EGW based nanofluids show higher friction factor when compared to the 40EGW based nanofluids which can be attributed to density and viscosity of the nanofluids. © 2018 PENERBIT AKADEMIA BARU.