His resignation has been accepted, Board Secretary Anurag Thakur told PTI. Sawani will
now serve a one month notice
period.
Sawani had set up BCCI's anti-corruption unit in 2012 after his similar stint with the sport's governing body ICC.
He reportedly wanted to quit in April but was asked to carry on until the end of IPL.
Neeraj Kumar, who was recently roped in as advisor to BCCI's anti-corruption unit, is tipped to replace Sawani.
Kumar, a former Delhi Police commissioner, had led the spot-fixing investigations in 2013, leading to the arrests of then Rajasthan Royals players S Sreesanth, Ajit Chandila and Ankit Chavan.