Many active secretions produced by animals have been employed in the development of new drugs to treat diseases such as hypertension and cancer. Snake venom toxins contributed significantly to the treatment of many medical conditions. Snake venoms are the secretion of venomous snakes, which are synthesized and stored in specific venom glands. Many toxins from snake venom are investigated and formulated into drugs for the treatment of conditions such as cancer, hypertension, and thrombosis. Most of the venoms are complex mixture of a number of proteins, peptides, enzymes, toxins and non-protein inclusions. Cytotoxic effects of snake venom have potential to degrade and destroy tumor cells. Different species have different types of venom, which depends upon its species, geographical location, its habitat, climate and age. The purpose of this chapter is to review focusing on the therapeutic potential of snake venoms and to establish a scientific basis for diseases treatment particular antitumor.