This study was conducted on forty male patients aged 17-35 years, suffering from migraine. Platelet aggregation was evaluated in them twice, once in the aura and headache phase of migraine and the other during the period in which patient was asymptomatic. We observed significant increase in platelet aggregation during the aura and headache phase of the migrainous attack in comparison to the headache-free interval. Platelet hyperaggregability may be an important factor in the pathogenesis of migraine.