Meterological factors influence several biological functions. Geomagnetic activity (GMA) can be considered a trigger factor of migraine attacks. We studied the possible relationship between 40 migraine patients and some meteorological factors: humidity, temperature and geomagnetic activity in particular. All frequency changes of geomagnetic activity, temperature and humidity values are recorded daily. The study was performed from March to June 1988 over a geographically small area in order to avoid climatic and environmental influences. Our results indicate a significant correlation between geomagnetic activity and migraine attack frequency. Controversial opinions concerning the modalities of data collection and the possible relationships between environment and headache raise the need of further studies.