Line 5 of the Saint Petersburg Metro, also known as Frunzensko-Primorskaya Line or Purple Line, is a newest rapid transit line in Saint Petersburg, Russia, opened in 2008, which connects the historical city centre to the northwestern and southern districts. It has 15 stations covering a total length of 26.2 kilometres (16.3 mi). Although it opened on 20 December 2008, parts of the line are considerably older. At its official opening in 2008, it included only two stations that opened concurrently with the line. On 7 March 2009, the Metro incorporated six existing stations of Line 4 (Pravoberezhnaya) into Line 5, expanding it to nine stations.

The Saint Petersburg Metro is a rapid transit system in Saint Petersburg, Russia. Construction began in early 1941, but was put on hold due to World War II and the subsequent Siege of Leningrad, during which the constructed stations were used as bomb shelters. It was finally opened on 15 November 1955.