Poland is a republic with a parliament.
Poland ( Polska [ ˈpɔlska ] ) , officially the Republic of Poland ( [ Rzeczpospolita Polska , links = no ] , ) , is a parliamentary republic in Central Europe . Sejm . Since the Second Polish Republic ( 1918 -- 1939 ) , `` Sejm '' has referred only to the lower house of the parliament ; the upper house is called the Senat Rzeczypospolitej Polskiej ( `` Senate of the Republic of Poland '' ) .