Captain Arturo Prat Base (Spanish: Base Naval Antártica "Arturo Prat") is a Chilean Antarctic research station located at Iquique Cove, Greenwich Island in the South Shetland Islands, Antarctica.

Opened February 6, 1947 by the First Chilean Antarctic Expedition, it is the oldest Chilean Antarctic station. Until March 1, 2006, it was a base of the Chilean Navy, on which date it was handed over to the regional government of Magallanes and Antártica Chilena Region. Until February 2004, it had been a permanent base. Afterwards, it had served as a summer base for ionospheric and meteorologic research. There have been plans to reopen the station for permanent occupation starting March 2008. The base is named for Captain Arturo Prat, a Chilean naval officer.

The climate is maritime polar (Köppen: ET), being on the coast of the peninsula with less severe averages than expected in Antarctica. Extreme temperatures can reach −29 °C or −20.2 °F in July, which is still quite bearable to humans protected due to considerable moderation of the sea, and a rare heat wave caused the temperature to reach 19 °C or 66.2 °F, a relatively high value. The climate is quite humid for its location and precipitation is fairly well distributed, so that even in the driest months it receives more precipitation than almost all of the Mediterranean zone.