Work will start on site early next year to transform the block into 100,000 sq ft of Grade A office accommodation to be named One Grand Central.
The job is due to complete in 2015 and is the first major new office building at the station following its £600m transformation.
Cannock’s Mike Tracey said: “Without doubt this is an exciting and significant project for the Cannock Group in Birmingham and we are delighted to have been appointed to bring forward One Grand Central.
“A complete back to frame refurbishment of the building will ensure that this landmark building is highly attractive to modern office occupiers at a time when the quantity of quality office stock in the city is diminishing.”
Chris Montgomery, Network Rail project director, said: “This planning application marks another important milestone in our extensive project to redevelop Birmingham New Street station.
“When complete, the new offices will have unrivalled travel connectivity, with the new integrated station incorporating the city’s metro extension right on the building’s doorstep.”