This study investigated the effects of cell phone exposure on the fatty acid composition in phospholipids, malondialdehyde concentration, p53 immune reactivity and histological structure of the rat brain. Sixteen Sprague-Dawley rats were divided into two groups of eight, sham and experimental (speech conditions). The rats were confined to Plexiglas cages, and cellular phone were placed 0.5 cm under the cages. For the experimental group, cellular phones were activated 20 minutes per day, 7 days a week, for 1 month. For the sham group, the cellular phones were placed beneath the cages with the phones turned off. The Whole Body Average SAR (rms) was 0.52 W/kg and 1 g averaged peak SAR (rms), 3.13 W/kg. The Mann-Whitney U-test was used for statistical. comparisons of groups.. Histological alteration and changes in brain phospholipid fatty acids composition were not observed in rat brains. Immunohistochemical staining of brain tissue shown that p53 immunoreactivity was not affected by cell phone exposure. Malondialdehyde concentration in exposed brains was significantly higher than sham (p < 0.05).