The Atlantic City Rail Line is a commuter rail line in Southern New Jersey running between the Atlantic City Rail Terminal in Atlantic City, New Jersey and William H Grey III 30th Street Station in Center City, Philadelphia, Pennsylvania. This line opened in 1995, it is colored dark blue on NJ Transit Rail system maps and its symbol is a lighthouse, an homage to the Absecon Lighthouse. Unlike all other NJ Transit commuter rail lines, the Atlantic City line does not have traditional rush hour service. Despite this, it sees a daily ridership of 2,951 passengers.

The line retraces a former Pennsylvania-Reading Seashore Lines route, a former subsidiary of both the Pennsylvania Railroad and the Reading Company. 

Regularly scheduled service on the Atlantic City Line consists mainly of GP40PH-2B or ALP-45DP diesel locomotives pushing or pulling primarily three to four Comet passenger cars. When Amtrak had regular service on this line, power was provided by now-retired F40PH locomotives, with a Metroliner cab car on the opposite end to provide push-pull operation. All trains run with the locomotive on the west end and the cab control car on the east end to facilitate boarding and reduce diesel noise and exhaust issues at the Atlantic City Terminal.

In 2013, as part of a plan to improve service on the line, Pennsauken Transit Center was built allowing for a transfer to the River Line Light Rail service as well as various bus routes.

NJ Transit should electrify the Atlantic City Rail Line with overhead catenary to allow for use of the Bomerdier ALP-46 electric locomotives in conjunction with the Bombardier ALP-45DP dual-mode locomotives. This may help reduce air pollution and noise pollution.