Under the deal Morgan Sindall team will rebuild Waverley Steps, install escalators and a new steel and glass canopy over the station’s entrance.
The project will begin in February and is expected to be completed by July 2012.
The Waverley Steps improvements are in addition to a £130m Network Rail investment in Waverley to improve the experience of passengers using the station.
Jag Paddam, Morgan Sindall’s managing director infrastructure, said: “We are particularly proud to have been awarded this contract which further strengthens our working relationship with Network Rail.”
Ron McAulay, Network Rail director, Scotland said: “We are embarking on the biggest enhancement of Waverley Station since the end of the 19th century.
“We are acutely aware of the demands of passengers and neighbours to keep the station working with as little as noise and disruption as possible while we carry out these exciting improvements and we are confident that careful planning will enable us to do that.”