Cisplatin is a potent anticancer drug which has been in use against a variety of cancers for a long time. The present study was carried out to assess the protective ability of ascorbic acid on cisplatin-induced mutagenic effects in tumor-bearing mice. The increase in the frequency of chromosomal aberrations, micronuclei and sperm abnormality were studied as markers of mutagenicity. Indicators of oxidative stress relatives like lipid peroxidation, reduced glutathione and the activities of enzymes such as catalase, glutathione-S-transferase and glutathione reductase were also studied to understand the possible mechanism(s) underlying this amelioration. Pre-treatment with ascorbic acid in combination group significantly reduced cisplatin-induced mutagenicity, markedly decreased lipid peroxidation along with increased level of glutathione and activities of antioxidant enzymes particularly in the liver of mice. The overall studies suggest that ascorbic acid with its antioxidant and free radical scavenging properties may play a part in its protective role in the abatement of cisplatin-induced mutagenesis and oxidative damage in the normal tissues of mice.