A series of experiment were performed to test the tribological properties of Si3N4 ceramic pair lubricated by emulsions of alcohol, acid and alkane. The experiment results showed that the function group can’t improve ceramic lubrication, which is reverse to metals. Under the condition of same carbon-chain, the lubrication by alkane is better than alcohol and acid. With the friction curve and wear scar diameter analysis, the paper studied the tribological properties of alcohol interfacial film. On the basis of above, hydrophilcity was involved to find the lubricating mechanism of emulsions.