The problem of halitosis is often found in all ages. It is one of the main causes of bad personality. The problems and bad breath are caused by bacteria that accumulates in the oral cavity from the eating behavior. The method to remove the smell, mainly is the use of chemicals because the chemicals have cytotoxicity more than biological agents as herbs Therefore, this study will test the efficiency of the ethanol crude extract by using ethanol from Clausena cambodiana Guill using the disc diffusion (disc diffusion method) to inhibit bacteria in the oral cavity .The experimental results show the inhibition of bacteria in oral cavity when tested with ethanol crude extract at concentrations 12.5, 25, 50, 100 . In conclusion, extracts crude ethanol from Clausena cambodiana Guill can inhibit the bacteria in the oral cavity.