The province of Cagliari (Italian: provincia di Cagliari; Sardinian: provìntzia de Casteddu) was a province in the autonomous island region of Sardinia, Italy. Its capital city was Cagliari.
It had an area of 4,470 square kilometres (1,730 sq mi), and a total population of 543,310 (2001). There were 71 comuni (sg.: comune) in the province [1].
The historical province was suppressed by the 2016 Regional Decree Province of Cagliari and replaced by the Metropolitan City of Cagliari.