Migraine headaches are very frequent and its prevalence rates between 15-18% in women and 5-6% in men (1). Migraine attacks vary very mach in their intensity and frequency from patient to patient, and during the time in same patient. Even 75% of the patients describe attacks as heavy or extremely heavy. Although somatic and neurology exams between attacks reveal regular findings, migraine can have great impact on the patients quality of life (social limitations, complications caused by drugs, psychiatric and somatic morbidity (2) In spite usual believes headaches are very often in children. Before puberty boys safer more frequently than girls. Just the same, in early childhood as well as in adolescence migraine pain could mimic and compromise bringing up the right diagnosis of the other possible somatic causes, most likely one sided headaches. Our case presentation points out one of the possibilities. L.M 15-years old patient hospitalized on the pediatric department of the ,,Kralj Milutin Clinic,, in Laplje Selo on October 2007, under the diagnosis of blanking out and left sided headache. After neurology exam and neurology diagnostic procedures done MR cerebra and MR-angiography, diagnose of aneurism of right the ACM (arteria cerebra media) has been established, and operatively treated. After the intervention, patient stays without intensive headaches , only weak pain on the left side of the head, now and on, without blanks.