The development, which is expected to create 3,000 jobs in the city, will also include a new library, residential units, office space and F&B outlets.
Limerick Twenty Thirty, the body charged with delivering the scheme, says its plans will protect all architecturally sensitive buildings on the existing site.
The Granary on Michael Street will be preserved but transformed internally, predominantly for office but also food and beverage use. Michael Street will also get a six-storey new build that will accommodate office, innovation, education, retail and food beverage space.
Another parcel, on the corner of Patrick Street and Ellen Street, will see residential, an aparthotel, retail, and food and beverage space developed across a five-storey new-build and an existing four storey structure. There will also be further opportunities for residential in the Georgian building on Rutland Street, with the ground floor of the building reserved for retail.