Abstract: Steroid myopathy (SM) occured in 25(12. 3%) of 204 patients with brain tumors who received steroid therapy and most of them developed weakness during the 4th through 7th week of continous steroid treatment. Wilcoxon test showed that there was no significant difference in the cumulative steroid dose between patients with SM and the patients without SM. It suggested that differences in individual susceptibility to the effects of steroid play a major role in the occurence of SM. The risk of developing SM was significiently lower in patients taking antiepileptic drugs (7. 9% ) than in patients who were not taking antiepileptic drugs.