Beckham, with £135million to his name, trails Wigan owner and JJB Sports founder Whelan.
The list, in the Sunday Times, only includes retired or active sports figures and 74-year-old Whelan, with a personal fortune of £190m, qualifies as a former professional footballer.
Whelan played for Blackburn and Crewe between 1956 and 1966 before retiring to focus on his chain of supermarkets which he sold to Ken Morrison for over £1m. He set up JJB Sports 1977.
But he has also advertised some of the world's biggest brands, including Adidas, Pepsi, Gillette, Vodafone, M&S and Brylcreem.
SPORT RICH LIST:
1 Dave Whelan (football) £190
2 David Beckham (football) £135m
3 Tony O’Reilly (rugby) £120m
4 Johnny Dumfries (motor) £110m
5 Lennox Lewis (boxing) £95m
6. Eddie Irvine (motor) £80m
7 Jody Scheckter (motor) £60m
8 Dave Richards (motor) £58m
9= Lewis Hamilton (motor) £50m
9= David Coulthard (motor) £50m
9= Nigel Mansell (motor) £50m