The Hollywood star topped Forbes’ annual list after making $239m (£185m) between June 2017 and June 2018.
Clooney’s pre-tax earnings were the most any actor in history has made over a 12-month period, the magazine said.
His massive income was largely from the sale of the tequila company he co-founded – Casamigos – to global liquor company Diageo in a $1bn (£790m) deal.
Wrestler-turned-actor Johnson was second on Forbes’ list after nearly doubling his previous year’s earnings, making $119m (£92m).
Meanwhile, Iron Man star Downey Jr came in third with his income of $79m (£61.2m).
The top six highest-paid actors each made more than the top-earning actress, Scarlett Johansson, who took home $40.5m (£31.4m) last year.
Click on the images of the top 10 earning actors below to reveal how each one made their fortune.