He was born to Chimri A. Sangma and Dipchon Ch. Marak. He had 6 siblings. A Salesian Father Giovanni Battista Busolin helped him in continuing his studies. He married Soradini K in 1973. The couple is blessed with 4 children including two sons and two daughters. His daughter Agatha is a politician whereas his another daughter Christy is not into politics. His both sons are into politics. His son Conrad is the Chief Minister of Meghalaya whereas another son James is also an active politician and home minister for the state.