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The stem cell marker CD133 has been sporadically investigated in meningioma, but because of the rarity of malignant meningioma (WHO grade III), only 7 malignant meningioma specimens have been included in previous studies. We investigated CD133 expression using the AC133 antibody clone in a consecutive cohort of 38 malignant meningiomas. Our results showed few, small CD133-positive hot spots with a pattern dominated by membranous staining and capping of the proteins without any nuclear CD133 staining in 30 of the 38 tumors. We could not corroborate spatial co-expression of hot spots with the proliferative marker, Ki-67, and CD133 hot spots in adjacent slides, nor did we find differences between Ki-67 expression in CD133-negative and -positive tumor specimens (Fisher's exact test: p = 0.69). CD13-positive niches represented only 0 - 1% of meningioma cells in most of the malignant meningioma, while CD133-positive cells were undetectable in 21% of the whole-section tumor samples. We found stem cell niches in 79% of malignant meningioma specimens in our cohort.