In 1990, he became the President of Hubli Rural Unit of the BJP and in 1994, the Dharwad District Unit President of the party. He was elected to the Karnataka Legislative Assembly for the first time in 1994 and has been reelected as Member of the Legislative Assembly from Hubli-Dharwad Central constituency for four successive terms. In 1996, he became the BJP State Secretary and in 1999, he was chosen as the Leader of Opposition in the Assembly following the defeat of the BJP in the state elections. Shettar was the Leader of Opposition when S.M. Krishna was the Chief minister and effectively discharged his duties.