This will provide another route to and from the station for people travelling from the Wednesfield part of the city.
It is also expected to ease pressure during peak times at Horsley Fields traffic lights and on the new Network Rail/Virgin Trains passenger drop off/pick up area at the station.
Sun Street/Corn Hill has been closed since 2008 following safety concerns surrounding the grade II listed Steam Mill building. The building has been demolished as part of the £132 million Interchange project.
The road reopening also means the new Bailey Street taxi feeder rank for the station will become operational. Taxis will therefore no longer need to use Albion Street to queue.
Councillor John Reynolds, City of Wolverhampton Council Cabinet Member for City Economy, said: "People are gradually getting used to the new access arrangements for the station and the reopening of Sun Street/Corn Hill will help improve traffic flow.
"I would like to thank people using the station and residents nearby for their patience while the new access arrangements bed in during this transitional period."
The developments at the station as part of the city's Interchange improvements include a new entrance to the extended multi storey car park, which has increased capacity from 450 to more than 800 long stay parking spaces.
The old entrance to the multi storey car park on Railway Drive has been permanently removed.
Pedestrians can continue to access the station via the footbridge from Pipers Row, while National Cycle Route 81 remains in use along Railway Drive, although cyclists should take care as construction traffic is operating in the area.
The access changes are the first phase of a new-look station, with enabling works now underway for the main station works.
The new station building will benefit from an enhanced Birmingham New Street-style ticket office, larger passenger concourse, ample ticket barriers to ease flow onto and off platforms, and much improved retail and café facilities.
The overall Interchange project will eventually also see a Metro line extension running down Railway Drive to a new stop at the station.
Councillor Reynolds added: "There is now genuine excitement about full works starting on the new state of the art railway station building in the coming months.
"Ultimately, as well as encouraging more investment and boosting prosperity in the city, the Interchange will become the gateway to the city for people arriving off the national rail network, by bus or Metro."
- released: Tuesday 14 February, 2017