The present research work entitled Private Trade of the English Merchants and Decline of Bengals Economy, 1690-1765, i.e. from the English settlement in Calcutta up to the grant of diwani, is an attempt to narrate the gradual decline of Bengal economy by the entry of private English merchants. It is also an attempt to narrate the private trade of the Company’s officials, free-merchants, as well as interlopers, who had carried on this illegal trade in different marts of Bengal, without any licence of trade. Thus on the very outset, it should be borne in mind that the present research work does not narrate the east India Company’s trade in Bengal.