Halitosis is a very common disease that affects the majority of the population and is characterized by unpleasant odor during expiration. Anaerobic bacteria produce a range of malodorous substances including volatile sulfur compounds. To reduce oral malodor, the amount of oral microorganisms should be managed through brushing, scraping, and use of antibacterial agents. In this study, a mouthwash containing 0.05% cetylpyridinium chloride was tested on 22 candidates with oral malodor for two weeks to confirm oral malodor reduction through the use of antibacterial mouthwashes. Volatile sulfur compound measurements were significantly lower after using the mouthwash than before using it; thus, the mouthwash effectively reduced oral malodor.