The fourth annual Sunday Times Sport Rich List says that Ferguson, who has just led United to Premier League title glory, is now worth £34m.
The list is based on identifiable wealth, which includes land, property, other assets such as art and racehorses, or significant shares in publicly quoted companies, but which excludes bank accounts.
Former Sunderland and Ipswich boss Roy Keane, who used to play for Ferguson at United, is next on the list at £29m, followed by Arsenal boss Arsene Wenger (£29m).
QPR manager Harry Redknapp is worth £13m, good enough for ninth on the list, just behind his predecessor at Loftus Road, Mark Hughes (£14m).
Interim Chelsea manager Rafael Benitez has joined the list in joint-10th, alongside England boss Roy Hodgson and Martin O'Neill, with a fortune of £12m.
The richest Formula One drivers born or based in the UK have also been revealed and Lewis Hamilton leads the way among active drivers on £60m, an increase of £5m since last year.
Jenson Button has also added £5m to his total in the last year and is now worth £58m, while Scot Dario Franchitti, a four-time IndyCar champion, is worth £50m.