The aim of this study was to investigate the anticlastogenicity as well as the clastogenicity of Eryngium foetidumleaf (EF) using the in vivo mouse peripheral blood erythrocyte micronucleus assay. Eighty ICR male mice werefed AIN-76 diet supplemented with ground freeze-dried EF at 0.0%, 0.8%, 1.6% and 3.2% for 2 weeks priorto the administration of both direct-acting, mitomycin C (MMC), and indirect-acting, 7, 12-dimethylbenz(a)anthracene (DMBA) clastogens. Peripheral blood samples were collected from mice just before administrationof clastogen and at 24 and 48 h thereafter for MMC. Blood samples were collected at the same times and after72 h for DMBA. Then, reticulocytes in blood samples were counted using fluorescent microscopy. The resultsindicated that EF had no clastogenic effect in mice. All doses of diets supplemented with EF decreased the numberof micronucleated peripheral reticulocytes in all the MMC-treated groups in a dose dependent manner, butsignificant reduction was found only at 1.6% and 3.2% EF in the DMBA-treated groups. It can be concludedthat EF has no clastogenicity, but possesses anticlastogenic potential against both direct- and indirect-actingtypes of clastogen in mice.