In this book entitled "Phytochemical characterization and Anti cancer activity of Cucumis Sativus Linn, the plant Cucumis Sativus belonging to family Cucurbitaceae has been studied to compare and give detailed report on,preliminary phytochemical, isolation of active constituents and pharmacological studies. The present study concluded that two phytoconstituents were isolated from the leaves of ethanolic extract of Cucumis Sativus Linn and characterized systematically. The extract was screened for in vitro anticancer activity. The ethanol extract produced significant in vitro anticancer activity. It shows that triterpenoids present in extract may be possibly responsible for the anticancer activities.