Lipoprotein (a) is a cholesterol-rich plasma lipoprotein with a lipid composition similar to that of low-density lipoproteins (LDL). Many prospective and case-control studies identified elevated levels of lipoprotein (a) as a risk factor for premature myocardial infarction and stroke. Elevated lipoprotein (a) has been identified as a genetically determined risk factor for stroke in young adults, but only preliminary data are available on its role as a risk factor for ischemic stroke in infants and children.Fifty two children with arterial ischemic stroke and 78 age- and sex-matched healthy children were studied. Data of this study indicate that 26.9% of children with arterial ischemic stroke had high lipoprotein (a) levels in comparison with the age matched healthy control group.Measurement of lipoprotein (a) should be included in screening programs performed in young patients suffering not only from venous thromboembolism but also arterial ischemic stroke, in addition to other thrombophilic factors.