In an interview with the Financial Times, Kwasniewski said the Law and Justice party, which won the recent general election, was built on "anti-Communism, anti-liberalism and crossing out the achievements of the Third Republic," the democratic republic created after 1989.
He said making populist election promises is one thing, but running a government and managing the budget is another.
Kwasniewski, a former Communist, hands over office next month to Lech Kaczynski, the Law and Justice party leader who won last month's presidential election. The party also won the September parliamentary election and has established a minority government under Prime Minister Kazimierz Marcinkiewicz.
Ministers have already announced plans including clearing former Communist officers from police and security services and abolishing the post of minister for women, making Poland the only European Union country without such a position.