On his return he joined the military rising to the rank of second lieutenant and left in the weeks surrounding January 1943.
He went on to work in the Ministry of Finance until he was appointed to become the director general of Petroleum, Concessions, and Mines in April 1949.
After fleeing from Ayatollah Khomeini's regime in the 1979, revolution, Manucher Mirza permanently relocated to Venezuela, establishing a new life and a new business (potato crisp manufacturer) for himself.
In his later life he co-authored Blood and Oil: Memoirs of a Persian Prince with his daughter Roxane Farmanfarmaian, which was published in 1997.
In 2003, Manucher died in Caracas and was buried in Oakland Cemetery in Sag Harbor, New York next to his brother Abol-Bashar Mirza Farman Farmaian.