Earvin Johnson III, also known as EJ, was spotted holding hands with a male partner on the Sunset Strip in Los Angeles, and his father, currently part-owner of the Los Angeles Dodgers, confirmed the relationship.
The elder Johnson told the website he and his wife Cookie "love EJ, and support him in every way," adding, "We're very proud of him."
The younger Johnson, a student at New York University, said he's been "hoping and praying" for the Dodgers since his father and his business partners took over the franchise last year.
Magic Johnson, 53, revealed in 1991 he was HIV-positive and has since been known as a supporter of the gay and lesbian community.
In 2008, he called for the defeat of California's Proposition 8, which sought to ban same-sex marriages, US Weekly reported.