This paper represents method of producing biodiesel from castor oil (treated with mineral turpentine oil) by transesterification of the crude oil with methanol in the presence of NaOH as catalyst. This paper mainly involves “Esterification”. Factors effecting the biodiesel production (reaction temperature, reaction rate & catalyst) are analyzed. The esterification procedure converts castor oil to its methyl esters. Important fuel properties of methyl esters of biodiesel produced from castor oil like viscosity, flash point, fire point, calorific value etc., was found out and compared to the properties of Indian standard biodiesel. This paper study supports the production of biodiesel from castor oil as a viable alternative to the diesel fuel.