Abstract: The progress of research on CO low- temperature catalytic oxidation by Au catalyst is reviewed，and the effects of preparation method，the size of Au particle，support and preparation condition on the activity of Au catalytst are analyzed. The mechanism of catalytic oxidation is discussed. In general，the appropriate synthesis methods would be effective in controlling the catalyst particle diameter，and dispersing the catalyst on the carrier to achieve better catalytic activity. The appropriate calcination temperature and the appropriate type of carrier are also necessary for highly active catalyst.