Jacobus Balduinus (d. 1225), Italian jurist of the 13th century, was by birth a Bolognese, and is reputed to have been of a noble family. He was a pupil of Azo, and the master of Odofredus, of Hostiensis, and of Jacobus de Ravanis, the last of whom has the reputation of having first applied dialectical forms to legal science. His great fame as a professor of civil law at the University of Bologna caused Balduinus to be elected podesta of the city of Genoa, where he was entrusted with the reforms of the law of the Genoese republic. He died at Bologna in 1225, and has left behind him some treatises on procedure, the earliest of their kind.