Harden made the announcement Saturday with Houston Mayor Sylvester Turner. They spoke at a news conference at the NRG Center, which has housed evacuees since Harvey swamped the Houston area more than a week ago.
Harden went to high school in California and college in Arizona but said Houston is his home. He posed for photos with fans and said the money would go people who need it.
Oscar winners Sandra Bullock and Leonardo DiCaprio also have pledged $1 million to charities helping with Harvey relief.
President Donald Trump also pledged a $1 million donation, but it’s unclear who will get the money. The donation is expected to come from his personal fortune.
Trump also visited evacuees Saturday in Houston.