Torchitorio III[1] (died after 1188), born Peter, was the Judge of Cagliari from October 1163 to his deposition and arrest in 1188, after which he was never heard of again.

He invaded the giudicato and forced Peter to flee to the court of his elder brother Barisone II of Logudoro at Porto Torres.

In March 1164, the Barisone and Peter, united with the Pisans of the island, retook the city of Cagliari and then invaded Arborea in April.

In 1168, a treaty was negotiated by the Genoese diplomat Nuvolone Alberici between Genoa and Arborea on one side and Pisa, Logudoro, and Cagliari on the other.

The Pisans mercilessly assaulted Genoese merchants in Cagliari and despoiled their landed possessions, evicting them from the giudicato.

They encouraged Obert, Margrave of Massa, and his son, William, to invade Cagliari and establish Pisan authority.