A member of the Ba'ath Party, he served as Prime Minister of Syria in 1965 and again from 1966 to 1968.

After the 1970 coup, Zuayyin was arrested on November 13, 1970 and imprisoned for 11 years.

[2] He was released in 1981, being allowed to travel to the United Kingdom for medical treatment.

After his recovery, he lived in Hungary and Sweden.

Zuayyin died after a long illness on 10 January 2016 in Stockholm, Sweden at the age of 84.