Barbara Anna Nowacka (born 10 May 1975) is a Polish politician. A left activist in Labour United, and later in Your Movement, in October 2015 she became leader of the United Left coalition for the 2015 Polish parliamentary election, bringing together Labour United, Your Movement, the Democratic Left Alliance, the Greens, and the Polish Socialist Party. Nowacka is the daughter of the late Deputy Prime Minister and Minister of Social Policy Izabela Jaruga-Nowacka. Since 2016 she has been the leader of the Polish Initiative.