Hybrid nanofluids are gaining a wide range of applications clue to their reported improvement in heat transfer properties. This study presents an experimental investigation into the specific heat and viscosity of Al2O3-ZnO water hybrid nanofluids at three mixture ratios. The specific heat and viscosity measurements are taken over different temperatures at different volume concentrations. The study compared the experimental data to classical models and observed that the specific heat model overestimated and the viscosity model underestimated experimental obtained values. According to results, the particles mixture ratio has a significant effect on both specific heat and viscosity of the hybrid nanolluids. Viscosity increases while specific heat decreases by increasing the volume concentration. Al2O3-ZnO water hybrid nanofluids at 2:1 mixture ratio have a maximum viscosity increase of 96.37% and maximum specific heat decrease of 30.12% at a temperature of 25 C and volume concentration 1.67%. (C0 2020 Published by Elsevier B.V.