She will take over from director of comms Paul Burden when he retires in the new year.
Donovan left Granada in early 2004 ahead of its merger with Carlton to form ITV.
She is currently interim communications director at United Business Media.
Although John Lewis is a partnership, co-owned by its employees as partners, the City and business commentators see the company as a barometer for the state of the UK retail sector.
The group, which has just marked its 75th anniversary, comprises 27 John Lewis department stores and 173 Waitrose supermarkets, making it one of the UK's biggest retail businesses.
John Lewis's comments on this Christmas's trading period will attract a great deal of scrutiny in the new year.
Last week John Lewis said turnover had hit a new record in the week to 10 December, with total non-food sales up 7.1 per cent to £84.1m. Strong sales ahead of Christmas were led by electrical goods and home technology with MP3 players sold in heavy volumes.
Donovan was in the frame for the comms director job of the newly created ITV plc last year but left Granada before ITV appointed Dow Jones International head of comms Brigitte Trafford to the role in
As well as heading Granada's comms for five years, Donovan was director of PR for leisure group Rank for three years. She joined Rank from brewing and pubs company Bass in 1996.
As head of comms for John Lewis, Donovan will have control of the firm's relationship with retained financial agency Hogarth and several other agencies handling PR for different aspects of the business including upmarket food retailer Waitrose.
Waitrose sales increased 6.9 per cent in the same period to £73.49m.