Background: When compared to other stage IVA oral squamous cell carcinoma (OSCC) patients, pT4aN0 OSCC patients without pathological risk factors appear to have a better prognosis after curative surgery alone; therefore, the necessity of and indication for postoperative radiotherapy (PORT) in these patients is controversial. Methods: The medical records of all early-stage OSCC patients who underwent curative surgery between 2004 and 2009 were reviewed. Results and Discussion: A total of 555 patients, including 332 pT1N0 patients, 141 pT2N0 patients and 82 pT4aN0 patients, were enrolled in this retrospective study. More than one-third of the pT4aN0 patients (30/82, 36.59%) had undergone PORT. No significant differences were noted between the pT1-2N0 group and the pT4aN0 group with respect to 5-year disease-free survival or cumulative local or regional recurrence rates (p= 0.81, 0.93 and 0.88, respectively). Among the pT4aN0 patients, there were no significant differences in disease-free survival, overall survival, cumulative local recurrence, regional recurrence or distant metastasis rates between patients who had undergone and not undergone PORT (p= 0.3, 0.42, 0.42, 0.59 and 0.31, respectively). Multivariate analyses showed that PORT did not provide an additional survival benefit for either disease-free survival or overall survival (HR=1.77 (0.89-3.53), p= 0.1; HR= 1.53 (0.64-3.67), p= 0.34) Conclusions: pT4aN0 OSCC patients without pathological risk factors exhibit a good capacity for disease control and good survival after curative surgery alone. Postoperative radiotherapy did not provide additional benefit for locoregional disease control or survival.