Thermohydraulic performance analysis of a wavy, tapered, double-layered microchannel heat sink is done numerically. The coolant used is water with temperature-dependent properties in single-phase flow considering Reynolds number in the range of 100–500. Uniform heat flux at the base of the microchannel heat sink is applied. The study suggested that the tapered, wavy channel has given better thermal performance than the straight, wavy channel; however, pressure drop has increased. Also, a comparison with a smooth, tapered, double-layered microchannel heat sink showed 13.6% enhancement on overall performance with wave [Formula: see text], [Formula: see text], Reynolds [Formula: see text], and tapering [Formula: see text] when all three plates of the double-layered microchannel heat sink are considered wavy. Moreover, it has also been observed that considering only the middle plate wavy, the cost of fabrication could be minimized and still similar enhancement over a smooth, double-layered microchannel heat sink could be obtained.