Cytotoxic and antiviral potential of ivermectin and ribavirin was evaluated. Cytotoxicity was checked on chick primary fibroblast cell line through MTT assay. Antiviral potential was determined against Newcastle disease virus on 9-day old chicken embryos. Six different concentrations (200, 100, 50, 25, 12.5 and 6.25μg/ml) of both the drugs were evaluated. The 100μg/ml concentration of ivermectin and higher were cytotoxic. The 25μg/ml concentration of ribavirin and higher were cytotoxic. Comparison of ivermectin and ribavirin showed that ivermectin was safe at 50μg/ml and lower concentrations. Ribavirin was protective for cell at 12.5μg/ml and 6.25μg/ml only. Comparison of antiviral activity indicated that ivermectin has strong antiviral potential at 100μg/ml and higher but same concentrations were cytotoxic. Ribavirin showed strong antiviral potential at all concentrations.