Piazza Martiri della Libertà, Historical square in central Pisa, Italy.

Piazza Martiri della Libertà is a rectangular plaza in central Pisa featuring a central statue of Grand Duke Pietro Leopoldo I mounted on a marble base with low relief sculptures. The plaza connects to several streets and provides pedestrian access to the nearby Santa Caterina church and cultural institutions.

The square occupies the site of the San Lorenzo monastery, profaned in the Napoleonic period and demolished around 1815. A 1817 competition was won by Tommaso Poschi, but his plan advanced slowly; in 1827 Alessandro Gherardesca was put in charge. A marble column stood at the centre until a statue of Grand Duke Pietro Leopoldo by Luigi Pampaloni replaced it, inaugurated in 1833.

The square was formerly called Piazza Santa Caterina, after the nearby church of Santa Caterina d'Alessandria. Its current name honours the martyrs of liberty. The marble base of the central monument carries reliefs by Emilio Santarelli and Temistocle Guerrazzi, showing the grand duke's work for agriculture and commerce and his protection of the arts.

The plaza is easily accessible on foot and serves as a junction to surrounding streets and attractions. It is an open space, so plan accordingly for weather conditions and find shade nearby if needed.

The square was long known as Piazza Santa Caterina, after the nearby church of Santa Caterina d'Alessandria. Its present name, honouring the martyrs of freedom, came later. The marble column that Gherardesca placed at the convergence of the paths in 1827 was meant to be replaced by a statue of Grand Duke Pietro Leopoldo, funded by a public collection begun in 1829.