Ricinus communis Linn. Family- Euphorbiaceae (castor oil plant) has been used widely as a contraceptive herbal drug in Nigeria, Africa and some countries in the Middle East. The efficacy of the seeds as a contraceptive drug has been confirmed by many scientists working independently in different locations around the world. With adequate information on the efficacy of these seeds, it became necessary to conduct a formulation study in order to develop a suitable and stable dosage form for this drug. The physical and chemical properties of the seeds used locally in Nigeria were determined and did not differ significantly from the properties of R. communis L. described in the African Pharmacopoeia. A total ash of 3.1% and alcohol soluble extractive value of 52.4% were obtained for the seeds while phyto-chemical screening revealed that the seed extract contained steroids and alkaloids. For safety and efficacy, the LD50 was determined and was found to be 13.17g/kg. The formulation studies revealed that 10 %starch mucilage was the best binder for the formulation of the granules while lactose at aconcentration of 75% was the best diluent for the drug. Characterization of the dosage forms produced showed that increases in compression pressure resulted in correspondent increase in the hardness, tensile strength, packing fractions and disintegration time. Administration of the dosage forms to albino rats, showed significant contraceptive activity (80%).