The Lincolnshire builder has already signed up Marks and Spencer as anchor tenant for a 35,000 sq ft store at the site on Doncaster Road.
It also will build around 40,000 sq ft of extra retail space and provide 550 car parking spaces as well as local road improvements.
Chris Newsome, development director for Simons, said: “This is fantastic news for Scunthorpe. We’ve seen a huge amount of support for the plans over the last few months, so we know the councillors’ decision will be welcomed by the vast majority of people in the town.”
Construction work will begin early next year with Simons, a specialist retail builder, taking the lead role.