© 2018 Elsevier Masson SASThe thermal and hydraulic performance of a heat sink having aluminum honeycomb fins is numerically investigated by using a finite-volume-based solver. The fin height (H), the distance between the fins in the streamwise direction (Sy) and the Reynolds number (Re) are selected as design parameters while the thermal resistance of the heat sink (Rth) and the pressure drop (ΔP) are regarded as the performance criteria. Each design parameter is examined in three levels and twenty-seven three-dimensional simulations are carried out in total. A computational domain consisting of three parts as the inlet and outlet sections and the test section where the honeycomb heat sink is located is used in the simulations. The CutCell mesh is employed for the test section while hexahedral meshes are used to discretize the inlet and outlet sections. The Reynolds-Averaged Navier-Stokes (RANS) based Realizable k-ε turbulence model in combination with the enhanced wall function is employed in the simulations. The effects of each design parameter on the performance criteria are examined in detail.