Modern synthetic medicines are very effective in curing diseases but also cause a number of side effects. Parasites are of concern to the medical field for centuries and the helminthes considered causing considerable problems for human beings and animals. To investigate the anthelmintic activity of Cajanus cajan. Dried powder was taken and subjected to successive extraction with petroleum ether, ethyl acetate, ethanol and water in soxhlet apparatus. The anthelmintic activity was evaluated on adult Indian earthworm pheritima posthuma due to its anatomical and physiological resemblance with the intestinal roundworm parasites of human beings. The earthworms were divided in nine groups, each group consisting of six earthworms of approximately equal size were released into 50 ml of the extract. Albendazole using as a standard drug, both alcoholic and aqueous extracts has shown significant anthelmintic activity compared to standard drug albendazole. The data reveals that the aqueous extract shown anthelmintic activity for paralyzing as well as death of Indian earthworm pheritima posthuma at 5mg concentration is of long duration of time, whereas the ethanolic extract showed paralysis and death at similar concentration in short time duration. The leaves of Cajanus Cajan Linn. Ethanolic extract has given potent anthelmintic activity as compared to standard drug, thus it is evident that leaves of this plant of daily use is useful for anthelmintic activity and it is concluded that further research is possible for finding active compound responsible for this activity.