Background/Aim. Etiology of ischemic stroke (IS) among young adults varies among countries. The aim of the study was to investigate the causes and risk factors of IS in the young adults of Serbia. Methods. A total of 865 patients with IS, aged 15 to 45 years, were treated throughout the period 1989-2005. Etiologic diagnostic tests were performed on the patient by the patient basis and according to their availability at the time of investigation. The most likely cause of stroke was categorized according to the TOAST (Trial of ORG 10172 in Acute Stroke Treatment) criteria. Results. There were 486 men and 379 women, with 19% of the patients ≤ 30 years old. Large artery arteriosclerosis and small artery disease were confirmed in 14% of the patients, and embolism and other determined causes in 20%. Undetermined causes made up 32% of the patients, mostly those (26%) with incomplete investigations. Smoking (37%), hypertension (35%) and hyperlipidemia (35%) were the most common risk factors. Rheumatic heart diseases and prosthetic valves were the most common causes of IS. Arterial dissections and coagulation inhibitors deficiency were detected in a small number of patients. Conclusion. Etiology of IS among Serbian young adults shares characteristics of those in both western and less developed countries.