As per WHO , there are very less anthelmintic drugs are used in Helminthes. For parasitic infection the anthelmintic from natural source may play an important role. Hence, this study was undertaken to evaluate the anthelmintic efficacy of Psidium guajava (L.) leaves extract against parasites. Phytochemical screening was carried out on ethanolic extract of Psidium guajava (L.) and then screened for its anthelmintic property against earth worm Pheretima posthuma. The effect of Psidium guajava leaves Extract and its fractions on the anthelminthic activity of piperazine citrate were also determined. PGE showed a dose-dependent anthelmintic activity against Pheretima posthuman.Anthelmintic activity of aqueous and alcoholic extract of leaves of Psidium guajava were evaluated separately with different concentraction on adult earth worm and compared with the standard drug piperazine citrate. The result found that extract exhibited, dose dependent action and inhibition of spontaneous motility (paralysis) and death of earth worm.