Background: Suicide is threatening self injury with informed aim, accounting for 0.4-0.9% of all cases of death. Among adolescents, suicide is the third leading cause and in young people, suicide is the seventh cause of death. Regarding to young population and increasing suicideal rate in recent years and time and cost required for recovery of patients, survey of suicidal causes is essential.Methods: In this cross-sectional study, we designed a questionnaire containing demographic and social objects and underlying causes of suicide. After daily going to hospital and interview with patients, results were collected. Data were analyzed by SPSS ver 9 software and X2 test with confidence interval 95%.Results: from 240 suicidal attempt, 98 cases (40.8%) were male and 142 cases (59.2%) were female. Most cases were 15-19 years (33.3%) and were educated in guidance school (30.4%). In 22.9% cases, there was history of suicidal attempt. Familial discord (54.6%), love related emotional disorder 918.8%), economic problems (8.3%), physical or psychological disorders (7.9%) and other predisposing causes (7.9%) were the major causes of suicide and in 2.5%, predisposing factor was not detected. There was significant difference between married and non-married and below 25 and more than 25 years old (Pvalue <0.05).Conclusion: Familial discord is the major risk factor of suicide that would necessitate the founding of consultation centers for adolescents and youths in order to meet their needs, answer their questions and give them guidance and support. Love-related emotional problems constitute the second most important factor that threatens young people. Thus, they should be persuaded to seek professional help and encouraged to frankly express their feelings to specialist in order that appropriate guidance be provided.