IN718 is widely employed as a surface functional coating material across various industries due to its excellent mechanical properties and weldability. Recently, multi-component ceramics (MC) have gained attention as an effective means to enhance IN718 coatings, owing to their novel strengthening mechanisms and superior reinforcement effects. An IN718/MC composite coating was fabricated using laser-directed energy deposition, and its microstructure and mechanical properties were systematically investigated. The results revealed that the ceramic phases in the MC materials decomposed in the molten pool under the combined influence of the high-energy laser and intense Marangoni convection. Solid-soluble elements such as W and V contributed to solid solution strengthening by integrating into the γ-Ni matrix, while free carbon, along with elements such as Nb and Mo, formed secondary carbides, promoting fine-grain strengthening. Additionally, eyeball-shaped Al 2O 3-TiN-NbC composite ceramic particles were observed at grain boundaries, providing a significant second phase strengthening effect. Owing to the synergistic contribution of these three strengthening mechanisms, the composite coating exhibited a 1.34-fold increase in microhardness and a 54.39 % reduction in wear volume compared to the pure IN718 coating. Quantitative analysis of the strengthening contributions revealed that solid solution strengthening was the dominant mechanism, contributing an increase of 59.52 HV in microhardness, while second phase strengthening accounted for an additional 10.95 HV. Furthermore, electrochemical tests showed a transition from uniform corrosion to localized pitting corrosion with increasing MC content, attributed to the formation of micro-galvanic cells within the highly conductive ceramic components, which accelerated the corrosion process.