During the invasion of Ukraine, Russia has attacked schools, hospitals and buildings where people have turned to seek refuge.
Roger Federer writes on social media that his foundation now makes a donation of 500,000 dollars, which is equivalent to 4.7 million kronor.
The donation is made to help Ukrainian children gain continued access to school.
"My family and I are horrified to see images from Ukraine and heartbroken for the innocent people who have been so horribly affected," he wrote on social media.
The American Tennis Federation also helps
40-year-old Federer has won 20 Grand Slam titles, one less than record holder Rafael Nadal.
Tour colleague Andy Murray has also announced that he will donate the prize money he earns this year to humanitarian efforts to help children in Ukraine.
At the same time, the US Tennis Federation announces that part of the ticket proceeds from the Billie Jean King Cup matches between Ukraine, led by former world three Elina Svitolina, and the US next month will go to a relief fund to help those affected by Russia's invasion of Ukraine.