The effect of Al2O3 nanofluids in a corrugated plate heat exchanger (PHE) were investigated in this study using computational fluid dynamics (CFD). Nanofluids have received attention recently as potential fluids to increase heat transfer in simple geometries, and work to investigate nanofluids in different systems is ongoing. In this study, a three-channel corrugated PHE with a width of 127 mm, length of 56 mm and channel thickness of 2 mm was investigated. The hot fluid in the system flows through the middle channel while the cold fluid flows through the two side channels. Three chevron angle configurations were considered for the simulation: 60 deg/60 deg, 27 deg/60 deg, and 27 deg/27 deg. Commercially available CFD software (ansys fluent) was used for the simulations. Numerical simulations were conducted for four Al2O3-water nanofluid concentrations: 1%, 2%, 3%, and 4% by volume. In addition, plain water was simulated for comparison. The simulation results show that although the thermal conductivity does increase with increasing nanofluid volume fraction, heat transfer decreases slightly with increasing nanofluid volume fraction. This decrease can be attributed to increased fluid viscosity with increasing volume fraction and the complex flow regimes of nanofluids in the three-dimensional geometries of PHEs.