Three Mo-Ni-Si metallizing coatings with various chemical compositions were deposited on SiC ceramic substrates by vacuum fusion sintering process, and the phase compositions of the coatings and their interface microstructure were analyzed. The wetting and spreading of molten Ag on the coated SiC ceramic substrates were investigated by the sessile drop technique, and the interfacial behavior of the Ag/coated SiC systems was analyzed and discussed. The experimental results showed that the coatings were mainly composed of Mo₅Si₃, MoSi₂, Ni₂Si, NiSi₂ and MoNiSi. The tetragonal MoSi₂ grains located on the coating surface disappeared with the concentration of Mo increasing from 20 at.% to 40 at.%. The final contact angles of Ag/coated SiC systems at 1000 oC for holding 30 min were 45o, 79o and 85o for Mo20-Ni32-Si48, Mo30-Ni28-Si42 and Mo40-Ni24-Si36, respectively. This result can be closely related to the interactions between the Ag drop and the microstructure of the three Mo-Ni-Si coatings. No visible reaction layers were observed at all the coating/substrate interfaces before and after the wetting tests.