The company said Northridge – currently chairman of betting group Paddy power – will step up to the role on 1 April
Lovering had chaired the retailer since 2003 and led its flotation on the London Stock Exchange in 2006.
Northridge is also a former chief executive of Gallaher, the maker of Benson & Hedges cigarettes.
Debenhams saw increased sales over the Christmas period but urged caution in the face of the return to the 17.5 per cent VAT rate and the uncertainty created by the impending general election.
Yesterday Lovering became chairman of Mitchells & Butlers, replacing Simon Laffin after Joe Lewis, the Bahamas-based billionaire.