Wetting behaviors of pure nickel and nickel-based alloys on sintered ZrB2-SiC ceramics and their interfacial microstructures were investigated in this presentation.The nickel-based alloys were mainly the commercial nickel-molybdenum-chromium products.The wetting and spreading properties were observed by a realtime thermal optical measurement system under flowing argon-5%hydrogen atmosphere.As temperature increased,the pure nickel cylinder sample had few changes before 1218℃ except for the thermal expansion in size.After that,liquid phase formed and spread on the ceramic substrate.