Zaidi returned to India in 1923. He taught at Aligarh Muslim University from 1923 to 1930, when he entered the service of the Nawab of Rampur, subsequently becoming the state's vizier or chief minister in 1936 and holding this position until Rampur merged with the Dominion of India in 1949.
A member of the Indian Constituent Assembly from 1947 to 1949, he became a member of the new Parliament in 1950 and a member of the Lok Sabha in 1952. He left Parliament in 1956 to become Vice-Chancellor of Aligarh Muslim University, returning as a member of the Rajya Sabha in 1964. From 1967 to 1969, he served on the Indian Committee of Inquiry on Communal Disturbances; also leading a goodwill mission to nine African and Asian nations in 1964 and heading the Indian cultural delegation to Afghanistan in 1965 for its Independence Week celebrations.[5]
Zaidi retired from politics in 1970, continuing to serve as director of several industrial concerns and a publishing house until 1977.