A B.Sc and LLM from Aligarh Muslim University, Masood is an agriculturist by profession. He was general secretary of Bharatiya Lok Dal between 1975 and 1977. He was elected to the 6th Lok Sabha for the first time on a Janata Party ticket in the post-emergency polls in 1977. He went on to become the treasurer of the Janata Parliamentary Party between 1979-80.
Masood was re-elected to the 7th Lok Sabha on a Lok Dal ticket in the 1980 polls. After being the chief whip of Lok Dal in 1982, he became the deputy leader of Lok Dal Parliamentary Party for more than a year. He was the member of the Rajya Sabha from 1986-89. From 1989-91, he was a member of the 9th Lok Sabha. From April–November 1990, he was Minister of Health and Family Welfare (Independent Charge) in the V P Singh government. In 1991 he was re-elected to the 10th Lok Sabha.
In the late eighties, he was associated with Janata Party and was its deputy Parliamentary party leader. In the nineties, he joined the Samajwadi Party. He was the member of the 14th Lok Sabha from 2004-2009. In 2010, he was re-elected to the Rajya Sabha.