Each of the mega-depots would cover at least 50 hectares but ideally the bigger the better, said the study's consultants.
The West Midlands has become a national leader in providing depots, but the consultants say the region must plan for a new generation of mega-depots if it is to remain competitive.
'Very large warehouses of up to 100,000 square metres can be expected to be demanded by the market in the near future,' says the study.
The move towards ever-larger warehouses reflects the decline in UK manufacturing and the growing volume of imported products, says the study.
Supermarket chains, a driving force behind the growth of mega-depots, are selling more and more non food items and are tending to source these from overseas, particularly in the Far East, to keep prices down.
The consultants identified eight broad 'areas of search' within the region for the five sites they propose.
Each depot would have several gigantic six storey high warehouses, each with up to 100,000 square metres - equivalent to 14 football pitches.
Most of the undeveloped land with the potential for warehousing has been designated as Green Belt and much is along the M6 toll motorway.
The study will feed into a revision of West Midlands planning policies - the Regional Spatial Strategy - which is now under way.
The Regional Assembly has not commissioned any consultancy work to examine the environmental impacts of these mega-depots.
The proposal was condemned by the Campaign to Protect Rural England, which says the study does not address the impacts on road congestion, nor the environment.
Although the mega-depots should be linked to a railway, it was acknowledged most freight will continue to arrive and leave by road.
Just one 50 hectare mega-depot would generate 1,500 lorry journeys a day - equivalent to one every minute over 24 hours.