Geomagnetic effects on concentrations of lipids in the rats' white substance, subcortical structure (neostriatum) and blood were studied. Lipids in the brain and blood samples were investigated with the thin-layer chromatography. Indices D, H and Z served as characteristics of the geomagnetic activity. On the days of magnetic disturbances counts of brain and blood lipids were found to alter. The results suggest that changes in concentration of lipids, phospholipids as the most important components of biomembrane in the first place, are liable to impact their metabolism and, consequently, adaptability of organism.