The Constitutional Party (German: Verfassungspartei), also known as the German-Liberal Party (German: Deutschliberale Partei) was the main representative of liberalism and national liberalism in the German-speaking parts of the Austro-Hungarian Empire during the 1860s and 70s.
It was a party of the German-speaking bourgeoisie, had anti-clerical positions and sought to defend the privileges of German-speakers vis-à-vis the rising national movements of the Slavic minorities in the Habsburg monarchy.
Afterwards it became the strongest political group in the Imperial Council (the parliament of the Cis-Leithanian, i.e. Austrian-dominated, part of the empire) until 1879.
It was weakened after the financial crisis of 1873, which added to the rise of the more radical German nationalist movement.
Former members of the Constitutional Party were later referred to as "Old Liberals" (Altliberale).