Babu started his political career through the
Kerala Students Union (KSU) in 1966. He was the first Chairman of Angamaly Municipal Council and the youngest Municipal Chairman then in
Kerala. He served as Director, Kerala Plantation Corporation and Kerala State Consumer Federation. Was Vice-Chairman, Kerala University Union; President, Youth Congress Block Committee, Youth Congress District Committee (1977) and District Football Association, Ernakulam; General Secretary, Ernakulam District Congress Committee (1982–1991); General Secretary, I.N.T.U.C.; Office bearer of several Trade Unions in Kerala. Founder of Fine Arts Society, Angamaly. Executive Committee Member, K.P.C.C. K. Babu was elected to the
Kerala Legislative Assembly for the first time in 1991 by defeating M.M. Lawrance of
CPM with a margin of 4946 votes from Tripunithura constituency. It was considered a major political change in the constituency, as Tripunithura was a known Communist (Left) bastion till then. Babu has represented Tripunithura since then in the Kerala Legislative Assembly as he was re-elected in the years 1991, 1996, 2001, 2006 and 2011.
Pinarayi Vijayan of
CPM alleged that Babu had won the seat with the help of
BJP votes. Babu denied those allegations and stated "The allegation against me that I won the election with BJP’s votes was a smear campaign. CPM members couldn’t accept people’s verdict and the defeat of their candidate." ==Minister==