Purpose: This study aimed to investigate the characteristics of patients attempting suicide and to analyze treatment determination factors for patients with mental illness who go to an emergency center for treatment. Methods: Data collected from 117 suicide attempters who visited Busan Regional Emergency Medical Center were analyzed using frequency, percentage, χ²-test with SPSS/WIN 15.0. Results: Only 31 cases consulted with the psychiatric department; the other attempters’ refused to consult (26.5%). Among the 31 attempters who consulted, 23 cases (74.2%) were suffering from depression. The most common reason (38.6%) suicidal attempters gave to refuse psychiatric treatment was “I’m not mad. I don’t need the psychiatric treatment.” Treatment determination factors for mental illness were religion (p<.001), past history (p=.017), financial satisfaction (p=.048), previous history of suicidal attempts (p=.006), sleep disturbance (p<.001), expression of suicide (p=.010), and type of leaving the emergency room (p=.020, p<.001). Conclusion: Results suggest that people frequently misunderstand psychiatric treatment which leads to their refusal to accept psychiatric treatment. Therefore hospitals need to develop standard guidelines and procedures for suicidal attempters with the collaboration of emergency and psychiatry departments. In addition, medical teams need to provide attempters appropriate information and encourage them to actively seek psychiatric treatment.