Pelargonium graveolens essential oil (PGEO) is an interesting plant extract. The ability of this oil to protect against genotoxicity induced by the anticancer drug doxorubicin (DOX) and its anticancer activity were examined. The following groups of mice were tested for genotoxicity: Group I, negative control; Group II, orally treated with 0.9 ml/kg PGEO; Group III, i.p. injected with DOX at 20 mg/kg; Groups IV-VI, animals received PGEO doses of 0.3, 0.6, and 0.9 ml/kg orally for 5 days, plus a single i.p. injection of DOX on the 5th day of treatment. Significant genotoxicity after DOX treatment was noted in bone marrow cells evidenced by increasing frequency of micronuclei, sister chromatid exchanges, and chromosomal abnormalities. Conversely, DOX did not affect spermatocyte chromosomes. PGEO showed no effects on any genotoxicity endpoints examined. Further, the oil was protective against genotoxicity induced by DOX. PGEO also displayed strong cytotoxic effects on all human cancer cell lines tested: HepG2, PC3, A549, A431, HCT116, and MCF7, with ~100% cell death at a concentration of 100 µg/ml. GC/MS analysis identified 27 compounds. The two major components were citronellol and geraniol which participate to a great extent with other components in the protective role of PGEO.