This study investigated the awareness of bad breath, using the self administered questionnaires, in order to get to the bottom of the bad breath problem among dental students and other students in some region. A total of 121 questionnaires were collected out of 128 questionnaires. Moreover, Oralchroma which can measure the degree of bad breath based on the pinpointed distinction of volatile sulphur compound was used, and the following conclusion was drawn. 1. 89.6% of respondents said that they thought that had the bad breath, whereas 7.8% said that they did not think that they had any bad breath. but the truth of the matter was that all of the respondents was confirmed they had any bad breath. 2. 95.6% of respondents said that they felt that they had the most serious bad breath right after they got up, and 61.1% said that they felt that the bad breath was mostly from the tongue. 3. Generally, it turned out that bad breath causing factors were found to have high correlation except H2S and $(CH_3)_2S$.