PURPOSE: The aim of this research was to explore the relationship between chewing ability and dental functional status, perceived oral health-related quality of life, and a number of background variables in a Vietnamese population. MATERIALS AND METHODS: The cluster stratified sample consisted of 2,805 dentate subjects aged =/> 20 years from urban and rural areas in Southern Vietnam. Chewing ability was assessed using a questionnaire that included questions on perceived difficulty with respect to eight foods and three questions of the Oral Health Impact Profile that were considered relevant. RESULTS: Only a minority reported serious problems with chewing ability (reporting difficult or very difficult to chew). The logistic regression analysis on chewing ability outcomes showed significant relationships between chewing ability and having =/> 10 teeth in each arch, having sufficient molar regions (=/> 1 molar posterior occlusal pair [POP] bilaterally) for hard and soft foods, and having sufficient premolar regions (=/> 3 POPs), especially for hard foods. In the hierarchical functional classification system, likelihood to report complaints on chewing ability appeared to discriminate in the branch "=/> 10 teeth in each arch." Likelihood at subsequent levels ranged from approximately 1.5 to 3. In the branch "