Peganum harmala Linn. is an important medicinal plant and traditionally used as analgesic, antihelmintic, antimicrobial and anticancer agent. As the herb is used widely in the traditional systems of medicine, it was thought worthwhile to undertake the standardization. The present study designed for determination of physico-chemical parameters, phytochemical screening and also its antioxidant activity. The quality control parameters like extractive of plant with different solvents, ash values, foreign organic matter, loss on drying and pH of aqueous solution were determined. The antioxidant activity was determined by DPPH free radical scavenging method. The results obtained from preliminary pharmacognostic standardization of seeds of P. harmala are very helpful in determination of quality and purity of the crude drug and its marketed formulation. The ethanolic, hydro-alcoholic and aqueous extracts of seeds of P. harmala showed potent DPPH free radical scavenging activity.