Objective: Suicide is among the main problems in society and is caused by many factors. These factors are different between developed and developing countries. This research was performed to investigate the epidemiological data related to patients who attempted suicide by poisoning in Tabriz, north west Iran. Materials and Methods: Throughout a four-month period, 300 self-poisoned patients (168 females and 132 males) referring to Sina educational hospital in Tabriz , were evaluated by a general psychiatrist and psychologist through interview and filling out a questionnaire. Results: The most common precipitating factor was family conflict followed by psychiatric disorder and unemployment. Medical illnesses, in particular physical handicaps, substance abuse, and other psychosocial stressors were also effective factors. Conclusion: Precipitating and clinical risk factors associated with suicide attempts in Iran resemble those described in literature, but with a few variations.