The earliest structure of the Palazzo d'Accursio originally began as the residence of the jurist Accursius, but over time, it incorporated and expanded to include adjacent buildings to house civic offices.
In the 15th century it was refurbished under the designs of the architect Fioravante Fioravanti, who added the Clock Tower (Torre d'Accursio).
In 1920, in a period of turmoil in Italy caused by the rise of the Italian Socialist Party in the wake of the end of World War I, and the initial violences of the Italian Fascist Party, numerous people were killed while a session of the local council was being held inside the palace.
Further, when news of the massacre in the square reached the meeting, Socialist politicians shot a member of the Liberal Party who also taking part in the council, killing him, while others were also wounded.
The Hall of the Communal Council, on the first floor, is where the Bolognese Senate met, and contains a gallery ceiling frescoed with Baroque-style quadratura by Angelo Michele Colonna and Gioacchino Pizzoli (1675–1677).