An epidemiologic investigation was carried out to determine the prevalence of symptoms of temporomandibular disorders in college students that aged 19-31 years. 460 students were investigated with a questionnaire from September to December 2006. The obtained results were as follows : 1. The prevalence of symptoms of temporomandibular disorders was 80.6%. 2. The most frequently complained symptom was headache and joint sound was the next one without distinct difference between men and women. 3. While the rate of occurrence of symptom of acute malocclusion decreased with age in men, that of TMJ pain during chewing or speech increased with age in women. 4. Symptoms including TMJ pain during mouth opening, chewing or speech, TMJ fatigue and acute malocclusion occurred significantly more frequently in women than in men. Contributing factors including resting cheeks on hands, stressful state, gum chewing, insomnia and clenching occurred significantly more frequently in women than in men. 5. There was a highly significant relationship between symptoms and contributing factors including resting cheeks on hands, stressful state, unilateral chewing, insomnia and clenching. 6. There was a highly significant relationship between symptoms and general personality.