Rooney slips in at No 18 in the annual rankings.
Golf's big two, Tiger Woods and Phil Mickelson, still lead the way as the best-paid global sporting icons.
The 'Fortunate 50' list is published each year in the USA by Sports Illustrated and takes into account earnings, endorsements, bonuses and appearance fees.
Rooney's five-year United deal at £160,000 a week has propelled him into the sporting stratosphere for the first time.
Woods took home £41million in the past 12 months - an £18m DROP on 2009-10.
Roger Federer stays third overall with a whopping £34m.