Due to the increased use of high heat flux electronic equipment, improving the heat transfer capacity and surface temperature uniformity of heat sinks have become a major concern. In this study, a novel confined slot jet impingement heat sink with discontinuous triangular ribs (CSJIHS-TR) in the wall impingement zone is proposed. The upper cover plate is angled to improve the ability of the heat sink to dissipate heat. A Cu-Al2O3/water hybrid nanofluid is chosen as coolant. The main structural parameters of CSJIHS-TR are optimized using multi-objective. The optimized CSJIHS-TR is investigated using the Re and φ of the hybrid nanofluid. The results show that the optimized CSJIHS-TR exhibits an improved heat transfer capacity. The optimized CSJIHS-TR achieves a 27.8% improvement in performance evaluation criterion (PEC) and a 91.0% reduction in temperature standard deviation (Tstd) compared to the confined slot jet impingement flat-plate heat sink (CSJIFPHS). As Re of the jet impingement and φ of the hybrid nanofluid increase, the heat transfer capacity and temperature uniformity of the optimized CSJIHS-TR increase; however, the flow resistance of CSJIHS-TR also increases. In addition, compared with the mononanofluid, the temperature uniformity and the heat transfer capacity of the CSJIHS-TR with hybrid nanofluid are significantly improved.