The codon 72 polymorphism of the p53 tumor suppressor gene has been investigated extensively for its association with various cancers around the world. However, its influence has not been elucidated in the Thai population. Therefore, a case-control study with 97 patients and 97 matched controls was conducted to elucidate the association between the polymorphic p53 and oral cancer risk in a Southern Thai population. The frequencies of the Arg/Arg, Arg/Pro, and Pro/Pro genotypes were 36%, 35%, and 29%, respectively in the controls and 33%, 45% and 22%, respectively in the patients. This study shows that there was no significant association between the p53 codon 72 polymorphism and oral cancer risk. There was also no link with respect to smoking or drinking habits. However, our data suggest that for individuals who were younger than 65 years old, the Pro/Pro genotype may offer some protection against oral cancer (OR = 0.13, 95%CI 0.04-1.10). This is the first report on p53 polymorphism and oral cancer in Thailand.