Plans for the Grade II-listed building will see it become home to a new cinema and family entertainment complex which is set to open its doors in 2015.
Morgan Sindall best-off competition from five shortlisted rivals to land the job.
The firm will work with local subcontractors and suppliers.
Firms wishing to express an interest in working on the project should send an email to [email protected]
Initial work will see contractors on-site carrying out pre-construction and enabling works to the shell and core of the building.
The fabric of the venue will be surveyed before preparatory works are undertaken to enable it to become a safe construction site.
Jim McMahon, Oldham Council Leader, said: “Today marks the start of the physical work that will see this amazing building returned to use.”
“The Old Town Hall is a fantastic regeneration project – rescuing an important and historic building that was at risk of being lost forever and using it to spark economic growth and provide the amenities we need.”
“Morgan Sindall has a great track record and experience in mixed-use regeneration schemes like this and their commitment to using the local supply chain, wherever possible, complements our Get Oldham Working campaign.
Barry Roberts, area director for Morgan Sindall said: “This is an exciting and ambitious project to be a part of and we’re looking forward to getting started. It’s encouraging to see the Old Town Hall being brought back into use through this inventive, resourceful scheme.”