The factors related to patient, professional and total delay in 161 oral squamous cell carcinoma (OSCC) patients attending for treatment at a university hospital in southern Thailand were investigated. About 42 and 20% of these patients had a patient delay of more than 1 month and 3 months, respectively. About half of the patients received proper management from health care professionals (HCPs) on their first consultation. Traditional herbal medication use was significantly associated with prolonged patient delay (hazard ratio [HR] 0.46, 95% C.I. 0.28-0.76). None of the variables investigated had a significant association with professional delay. Traditional herbal medication use also significantly prolonged total delay (HR 0.45, 95% C.I. 0.27-0.74). Buddhists had shorter total delay than Muslims (HR 0.68, 95% C.I. 0.49-0.95). The present study indicates that both patients and HCPs are responsible for the diagnostic delay. A health education campaign about OSCC and the use of traditional herbal medication is recommended to shorten patient delay. Continuing education on oral cancer and precancer for HCPs and clarification of the referral system are needed to effect a major reduction in professional delay.