Governor K Sankaranarayanan administered the oath of office to Awhad, the working president of NCP's Maharashtra unit, at the Raj Bhawan here.
Awhad was the only minister who took oath at the ceremony.
NCP, which is Congress' ally in the state government, has brought in Awhad to fill up the vacancy created by the ouster of Vijaykumar Gavit.
Gavit, a regional heavyweight, was expelled from NCP after his daughter Heena Gavit contested from Nandurbar Lok Sabha constituency on a BJP ticket. She went on to win the seat by defeating 9-term Congress MP Manikrao Gavit.
The Assembly elections in Maharashtra are due later this year.