Tahmasp I (1524-1576) was an influential Shah of Persia of the Safavid Dynasty.

Tahmasp came to power at the age of 10, when he succeeded to the throne of Persia in 1524 after the death of Shah Isma'il I. During his childhood he was weak and unable to exert control over his empire. This resulted in the uprising of the Qizil Bash tribesmen, an important part of the Safavid power structure. Upon adulthood, however, he was able to reassert the power of the Shah and control the tribesmen.

His reign was marked by foreign threats, primarily from the Ottomans and the Uzbeks. It was during this period of the Safavid history that the area of modern day Iraq was finally won by the Ottoman EmpireOttomans . In the year 1555, however, he regularized relations with the Empire through the Peace of Amasya . This peace lasted for 30 years, until it was broken in the time of Shah Mohammed Khodabanda .

He is also known for the reception he gave to the fugitive Mughal Emperor Humayun which is depicted in a painting on the walls of the Safavid palace of Chehel Sotoon . This meeting is also important because it strengthened the Safavid claims over the Mughal Empire.

He died in 1576 and was succeeded by his son, Isma'il II