Congress nominee and Meghalaya Education Minister Ampareen Lyngdoh defeated United Democratic Party (UDP) candidate Malcolm Tariang.
Lyngdoh polled 5,800 votes over Tariang's 3,473 votes.
"I won despite personal attacks by my opponents. I must say they are yet to learn the game (of politics)," Lyngdoh said.
The four other candidates - Stephen Nongbet (BJP), Remeo Phira Rani (Hill State Peoples Democratic Party) and two Independents, George Garry Lyngdoh and Andrew Aibok Jyrwa, forfeited their security deposit.
The seat fell vacant when Lyngdoh resigned as UDP MLA and joined Congress.
With this win, the strength of Congress has gone up from 26 to 27 in the sixty-seated house.