The pub is located on the ground floor of the Metro Central Heights building on Newington Causeway.
Metro Central Heights - formerly Alexander Fleming House - is grade II listed and was designed by Erno Goldfinger.
The pub first opened 23 years ago when the former Government office building was converted into flats.
New features installed as part of the refit include a carpet inspired by the famous marble floor at Wentworth Woodhouse, the South Yorkshire family home of the Marquess of Rockingham.
The carpet design also incorporates a silk weave pattern and feather plumes as a reference to the Tarn & Co department store that once stood on the site of the pub.
Custom-designed glass racks above the bar with reeded glass are said to be an allusion to the original Victorian Rockingham Arms which stood on the corner site today occupied by The Elephant & Castle pub.
Pub manager Charbel Mikhaiel said: “Wetherspoon has spent £1.5 million on the pub, providing further substantial investment into the area, as well as creating new jobs for local people.
“Myself and my team will look forward to welcoming customers back into The Rockingham Arms and we are confident that they will be impressed by the new-look pub.”