Work is due to start on Fleming Way, between its junctions with Prince's Street and Station Road, in 2016.
It will see the elevated section of the road lowered to pedestrian level and an "uninviting" subway removed.
The project is being run by Forward Swindon, which is leading the regeneration on behalf of Swindon Borough Council.
Chief executive Ian Piper said the town centre was currently "split in two" by Fleming Way.
"[This makes] access to shopping and social facilities difficult for workers and visitors," he said.
"By removing this physical barrier, we will make Swindon town centre a more vibrant and attractive place to work and to visit."
Once the changes to Fleming Way have been completed the bus station will relocate to the western end of the road.
Developers say the area will include a "linear park" connecting the business district and the station to the north with shops and restaurants.
The redevelopment of Fleming Way and the surrounding area is the latest stage in the Kimmerfields development in the town centre.
Forward Swindon is an independent company established and funded by Swindon Borough Council in 2010 to "deliver and facilitate economic growth and property development in the town".
Part of one of Swindon's busiest roads will be turned into a bus-only route as part of a £350m town centre revamp.