The Nanjing Ring Expressway (Chinese: 南京绕城高速公路), designated as G2503, is ring expressway in Nanjing, Jiangsu, China.

[1] The first section was opened to traffic on 7 October 2005 which included opening of the Nanjing Dashengguan Yangtze River Bridge.

[2] The Ninglian Expressway (Ninghuai Expressway) section was opened to traffic 18 in December 2006, the southeast section was opened to traffic on 30 September 2010, and the whole expressway was opened to traffic on 24 December 2012.

[3][4][5] Several sections of the expressway run concurrently with the G25, G40 and G42 expressways.

Note: italic indicates the routes that were available in 2013 network plan, but removed in 2022 network plan