He first became the chief minister of Uttar Pradesh in June 1991.He was an important player in Sangh parvivar's Ayodhya movemenr.Kar Seva was supposed to be conducted in Ayodhya on December 6,1992 and he filed an affidavit in the Supreme court that as the chief minister of Uttar Pradesh, he will not allow any damage to the mosque.However Kar Sevaks demolished Babri mosque on that day. Taking the moral responsibility,he resigned from the post of Chief Minister of Uttar Pradesh in the evening.Later Union government dissolved Uttar Pradesh assembly.
He contested assembly elections to Uttar Pradesh assembly in November 1993 from two constituencies, namely Atrauli and Kasganj and won from both.As Samajwadi Party-Bahujan Samaj Party combine formed the government in the state under the cheif ministership of Mulayam Singh Yadav, Kalyan Singh served as Leader of Opposition in the assembly.
Kalyan Singh has recently been appointed as a Vice-President of Bharatiya Janata Party. He has one son, Mr. Raj Vir Singh, who was also a Member of Legislative Assembly for one time. He lost last assembly election in 2007 from Dibai to BSP rival, Guddu Pandit. He remain Health Minister of the state for about 6 months during Mulayam Singh Yadav Government (2003-2007). His wife Mrs. Premlata Verma is a sitting MLA from Atrauli Assembly Constituency.