Amaranthus viridis L. is a commonly growing herb, mainly used as leafy vegetable. The vegetable is a medicinal food used in urinary problems. Roots are known for its antifertility activity in Ayurveda. The term antifertility many times is used loosely in ethnic literature denoting abortifacient, antiimplantation and antiovulatory activity. Aqueous root extract was administered orally at the dose of 50 mg/kg, 100 mg/kg and 150 mg/kg body weight respectively for 5 days from 11-15 days of pregnancy to female albino rats. The results show that the antifertility effect is expressed as abortifacient activity which is dose dependent increasing with higher dose.