Plasmodium vivax is a digenetic malarial parasite which completes its life cycle on two hosts-mosquito (primary host) and man (secondary host). The life cycle of Plasmodium in mosquito called sporogony and in man schizogony. Schizogony includes three stages of which pre-erythrocytic and exo-erythrocytic schizogony takes place in RBC of blood of man which characterized by the formation of signet ring stage and schizont.