The striker, whose wealth has increased from £45m last year, is £9m better off than Manchester United team-mate Rio Ferdinand.
Rooney and his wife Colleen are jointly worth £64m.
The striker and centre-back Ferdinand are two of 24 current Premier League players among the 100 wealthiest sportsmen in Great Britain and Ireland, according to the list which is published tomorrow.
David Beckham unsurprisingly tops the lot with a £165m fortune.
Michael Owen (£38m) is third among the Premier League players, ahead of Ryan Giggs and Frank Lampard (both £34m).
Six Manchester United players are on the list, including Paul Scholes, Michael Carrick and Robin van Persie, who is a new entry with £12m.
Steven Gerrard is Liverpool's richest player with a £33m fortune, with Carlos Tevez (£18m) the richest Manchester City player on the list.
But their wealth pales in comparison to that of former England captain Beckham, now playing with Paris St Germain, who is the richest sportsmen in Britain.
He sits 11th on the Sunday Times World Sport Rich List, which is headed by Tiger Woods, worth £570m.
Beckham's joint wealth with wife Victoria is rated at £200m.
There are two other footballers on the world top 20, Barcelona's Lionel Messi, worth £125m, and Real Madrid's Cristiano Ronaldo, worth £120m.
The Rich List is based on identifiable wealth, including land, property, other assets such as art and racehorses, or significant shares in publicly quoted companies. It excludes bank accounts.