The judging panel included representatives of Sheffield council, urban regeneration company Sheffield One and development agency Yorkshire Forward.
Sheffield One would not confirm which firms were on the shortlist, but said that CTP St James would develop the commercial office element. As well as providing 2350 m2 of office space, CTP St James will also develop a multistorey car park, restaurants, cafes, bars and 150 apartments.
Sheffield council chief executive Bob Kerslake said: "All four proposals were excellent but the panel agreed that the CTP St James submission was the winner in terms of quality, innovation and deliverability. Sheffield has an underprovision of first-class office accommodation in the city centre and this will help to address that."
The commercial element of the scheme is the final part of the Heart of the City to get the go-ahead.