The induction of chromosome aberrations by a common analgesic with antipyretic activity, Paracetamol, was investigated in vivo on bone-marrow cells of albino male mice. The drug was given orally or intraperitoneally in a single and cumulative dose series. The doses were the serial dilution of the highest one (400 mg/kg for intraperitoneal administration and 800 mg/kg for oral administration). Our study indicates that the cellular damage induced by Paracetamol leads to expression in chromosome aberrations such as gaps, chromatid breaks, acentric fragments and polyploid metaphases.