Medicinal plants form an essential part of indigenous pharmaceutical system. Costus species (Family: Costaceae), commonly called as spiral ginger or crepe ginger are important medicinal plants used in traditional system of medicine in India. These plants are used for their stimulant, carminative, diuretic, digestive and antiseptic properties. Some of the species of Costus are mainly used for treating diabetes. Species of Costus are known to contain a steroidal saponindiosgenin as a major bioactive component, which is utilized as a precursor for the synthesis of various drugs. The present study is taken up to quantify the amount of diosgenin present in rhizomes and leaves of three species of Costus (C.pictus, C.speciosus and C.igneus) using HPLC analysis.