The money will come out of revenue from Saturday's sold-out concert on Mars' 24K Magic World Tour.
"I'm very thankful to the Michigan audience for joining me in supporting this cause," Mars said in a statement. "Ongoing challenges remain years later for Flint residents, and it's important that we don't forget our brothers and sisters affected by this disaster. As people, especially as Americans, we need to stand together to make sure something like this never happens in any community ever again."
"With a grateful heart, the Community Foundation of Greater Flint is honored to accept this inspiring donation," President and CEO Isaiah M. Oliver said in a statement. "We know Bruno Mars' $1 million gift will be transformative to the children and families of Flint. He understands the issues faced by Flint citizens, and we are touched by his concern and generosity."
Mars' album "24K Magic" was released in November 2016 and has sold over 2 million copies. The second single from the five-time Grammy winning singer's album, "That's What I Like," debuted at No. 1 on the Billboard charts in January.