A new alumina-supported cobalt-nickel oxide catalyst for the synthesis of acetonitrile from ethanol and ammonia was prepared by coprecipitation-kneading method. The parameters influencing the reaction were studied thoroughly and an optimized process, which is running the reaction at 380 degrees C under atmospheric pressure while keeping the ammonia/alcohol molar ratio of 5 and GHSV of 1,163 h(-1), was obtained. Under the optimized conditions the catalyst reached its best performance when being on stream for 40 h, at which the yield of acetonitrile was 92.6%. Then the selectivity to acetonitrile decreased gradually but the yield of acetonitrile always remained higher than 81% within 720 h. The samples of the fresh and used catalyst were characterized by XRD, XPS, TEM, EDX and N-2 adsorption-desorption analysis. The results revealed that carbon deposition and formation of metal carbides from the active species in the catalytic runs led to the deterioration of the catalyst.