The top 100 includes athletes from 25 countries and their $5.96 billion combined earnings are up 5 per cent from the previous year when American boxer Floyd Mayweather was first with $430 million.
The cutoff to crack the world's 100 highest-paid athletes is $25 million this year, compared with $17.3 million five years ago.
Boxer Saul "Canelo" Alvarez was the highest-earning non-footballer on the 2019 list, with $94m in total - just $2m of which were through endorsements, meaning he had the same salary as Messi.
Messi is one of 38 non-American athletes on the list, with 62 U.S. stars in the top 100.
Serena Williams is the only woman in the top 100, earning $29.2m (£22.9m).
Forbes calculates the athletes' earnings by adding up their prize money, salaries and endorsements between June 2018 and June 2019.More news: Zakka Arrives in Lebanon, Slams Iran over 'Arbitrary Detention, Show Trial'
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Athletes from 10 sports made the top 100, with National Basketball Association stars leading the way. Russell Wilson (NFL player) $135 million 7.
Messi was one of 38 non-American athletes on the list, with 62 United States stars in the top 100.
Stephen Curry ($US79.8 million) and Kevin Durant ($USS65.4 million) also made the top 10.
France and Spain each had three athletes while Brazil, Canada, the Dominican Republic, Germany, Serbia and Venezuela all had two.
Messi, who scored 36 goals while leading Barcelona to the La Liga title this year, earned $127 million (£100 million) between his salary and endorsements to move up one spot on the list of the world's 100 highest-paid athletes.
It is the first time that a trio of footballers have ranked as the top three earners, while Messi becomes only the second footballer to top the rankings after Ronaldo.