Following the establishment of the British East India Company in the early seventeenth century, this company entered the economic circuit of Safavid Iran through a contract signed with Shah Abbas I in 1617. The company, which sought to acquire exclusive trade in Iran, soon encountered a competitor called the Dutch East India Company, who stole the lead from the English company in the field of trade in Iran, and the Dutch company took the first place in foreign trade of the Safavid Iran until the end of Shah Suleiman's era. The present study seeks to clarify the factors affecting Iran and the British East India Company during the reign of Shah Sultan Hussein using a descriptive-analytical method based on Iranian and non-Iranian sources. The findings of the present study show that the British East India Company was able to improve its trade relationship with Iran during a new contract with Shah Sultan Hussein and consolidate its position in Iran's trade. In this regard, factors such as the Shah's visit to the company's trading house in Isfahan, the merging of trading companies in England, and the strained relations between the Dutch East India Company and Iran during this era had a significant effect. In addition, the company monopolized Kerman wool export and was able to receive some arrears of revenue from Bandar Abbas's customs clearance.