Konrad of Mazovia (1187 - 1247) was Duke of Mazovia, son of Casimir II of Poland ("the Just") and Helen, princess of Moravia. After his father's death in 1194, he was brought up by his mother and in 1202 he received Mazovia and Kujawy. He married the Russian princess Agafia. In 1228 he brought the Teutonic Knights to Mazovia.

Preceded by: Vladislaus III Laskonogi

High-Duke of Poland first time 1228-1232

Succeeded by: Henry I the Bearded

Preceded by: Henry II the Pious

High-Duke of Poland second time 1241-1243)

Succeeded by: Boleslaus