The Â£200,000 work on Kingsway will include new signs, re-marking and remodelling of the road.
Safety barriers were installed after the death of Sgt Louise Lucas in March, to stop pedestrians crossing.
Another man was hit by a bus on 4 August, while Daniel Foss, 37, died in 2013.
Swansea council is also considering introducing a dedicated cycle track as part of the changes.
It said the work to prevent public transport travelling in both directions is a pre-cursor to more detailed plans to redevelop the route as a business district.
Following a number of deaths and serious accidents on a main route through Swansea, a new one-way system will be introduced in the autumn.