Manchester United forward Cristiano Ronaldo has reclaimed top spot in the list of the world's highest-paid soccer players from Lionel Messi, according to Forbes.

Ronaldo, 36, rejoined United from Juventus in August after 12 years away, while Messi has swapped boyhood club Barcelona to join Paris St Germain.

Forbes said Ronaldo, among the world's most popular athletes with over 500 million followers across Facebook, Instagram and Twitter, is set to make $US125 million ($A172 million) before taxes in the 2021-22 season, with $70 million ($A96 million) coming from salary and bonuses at United.

The rest will come from endorsements and partnerships with brands including Nike, Herbalife, Clear and his CR7 brand.

Messi, who topped last year's list, will be paid a salary of $75 million ($A103 million) with an additional $35 million ($48 million) from endorsements for total expected earnings of $110 million ($A150 million).

The Argentine's strike partner at PSG Neymar, who in May signed a new contract until 2025, is third on the list with total earnings of $95 million ($A130 million).

TOP 10 HIGHEST EARNERS IN WORLD SOCCER

(US DOLLARS)

Cristiano Ronaldo - $125 million

Lionel Messi - $110 million

Neymar - $95 million

Kylian Mbappe - $43 million

Mohamed Salah - $41 million

Robert Lewandowski - $35 million

Andres Iniesta - $35 million

Paul Pogba - $34 million

Gareth Bale - $32 million

Eden Hazard - $29 million