Despite its numeric designation, it was the fourth Shanghai Metro line to enter passenger service, opening on 25 November 2003.

[2] In 1998, Minhang District authorities signed a contract with Shanghai Jiushi Group to build the line.

[3] In 2000, Shanghai Jiushi Group signed a contract between Alstom to purchase trains[3] and started its construction.

In 2005, it was integrated with Shanghai Metro's ticketing system, which enabled an in-station interchange to line 1 at Xinzhuang station.

On 1 April 2015, a feasibility study for the extending of line 5 platforms, upgrading signals to support the use of higher-capacity six-car trains and renovation of tail tracks at Xinzhuang was approved.

[7] Due to these system upgrades, service on the existing line was cut back from Minhang Development Zone station to Jinping Road on 20 August 2018.

Passengers wishing to travel the entire length of the line needed to interchange at Dongchuan Road station.

This arrangement ended on 26 December 2020, now service on the branch line continues straight through to Xinzhuang With four-car trains from the branch line and six-car trains from the mainline running in mixed operation in the joint section between Xinzhuang and Dongchuan Road stations.

[11][12][13] During the trial operation of the southern extension section Shanghai Metro received complaints from residents of Pujiang Building on noise.

After over 500 days, and more than 1,000 switchovers, line 5 had a seamless cutover to the new signalling system with no interruption to normal service at the end of 2018.