For the treatment of cancerous cells in human body it needs to detect such medicine that kills the carcinoma cells without any adverse effects on human body. The anti-cancer drugs used previously exhibited relatively high toxicity not only to the tumour cells but also to the normal cells of the body part in which the cancer had developed. Currently assessment of pharmacological properties of plant has become one of the significant basic studies in biomedical sciences in recent years. In this context the present study was undertaken to evaluate the effect of Ficus religiosa plant leaves extract for cytotoxic study to calculate LD 50 value by using brine shrimp lethality (BSL) assay experimental method. The current research work was aimed to check the preliminary stage In-vitro cytotoxicity and anticancer activity of Ficus religiosa plant leaves with the help of Brine shrimp lethality bioassay experimental method. We concluded that if concentration of drug increases % Inhibition of cell line is also increases. The LD 50 value of the plant was found to be 61.06 μgm. It would be beneficial effects as anticancer use due to the easiness and low cost of Ficus religiosa leaves maintenance. This could accommodate the usage of this medicinal plant as anti- cancer. However, further study is needed to investigate the other anti-cancer mechanism of leaf extract.