The potential ability of the electric field to produce genotoxic effect is still a matter of debate. Indeed, limited data are available about chromosomal aberrations and other genetic alternations after exposure to electric field. Fourty five mature female albino rats Rattus norvegicus were subjected as three groups. Rats were exposed to continuous microwave (MW) radiation of 9.865 GHz for 30, 45 and 60 days. The same intervals were studied to show the effect of garlic, Allium sativum treatment in association with the MW exposure. Results showed a significant induction of the structural chromosomal aberrations; deletion, break, gap, end to end association, centromeric attenuation, ring chromosome and stickness in the bone marrow cells. Administration of 20mg/kg garlic daily suppressed in significant way the occurred aberrations. The present work suggested the in vivo radioprotective role and antimutagenic effect of garlic.