Mikołaj Sienicki of Bończa (c. 1521-1582) was a member of the landed gentry of the Kingdom of Poland. He held the office of chamberlain of the land of Chełm and was a notable politician of his period. Considered one of the best Polish political orators, he also held the title of marshal of the Sejm nine times. A Protestant, near the end of his life he became a member of the Polish Brethren and one of the major initiators of, and contributors to the Warsaw Confederation, which introduced new laws of religious tolerance in the Polish–Lithuanian Commonwealth, on a scale unimaginable in contemporary Europe.