The firm, which was Stirling-shortlisted for its Lewis Glucksman Gallery in Cork, will design the new store at the heart of a massive retail development for Hammersons.
The win comes after an extraordinary July, which had already seen the office win two competitions; the Photographers' Gallery in London and the Regional Museum in Coleraine, Northern Ireland.
The scheme also represents an interesting departure for the practice, which has very little experience in the retail sector.
Ann Humphries, director of retail development at the John Lewis Partnership, said: 'Hammerson has demonstrated an understanding of our brand values which is reflected in the exciting design concept and the practice selected.
'We are confident that the new building will provide a high-quality shopping environment for all our customers and be a new, landmark shop for Sheffield,' Humphries added.
Construction is scheduled to begin in 2008.