Johnson made the announcement on Twitter.
"I love the coaching staff as we've been building a strong relationship since I've been in the 7th grade," Johnson wrote. "They've always made sure I was a priority at all times and watched me develop from then to where I'm at now. This feels like home for me as I will have an opportunity to build my own legacy and have the dome rocking every night!!"
Johnson, a 6-foot-2 point guard who plays at Mayfair High School (California), is considered one of the most talented sophomores in the country. He is ranked No. 13 in the ESPN 25 for the 2022 class.
A native of Saugerties, New York, Johnson has bounced around to multiple high schools early in his career. However, he did score more than 1,000 points during his seventh- and eighth-grade seasons at Saugerties, before transferring to other high schools.
He began last spring playing for the Oakland Soldiers 17U grassroots program on the Nike EYBL, but he soon left the Soldiers to team up with Bronny James on the Strive For Greatness 15U team.
Johnson took multiple visits to Syracuse's campus and was expected to be on campus for the Orange's game against Duke last weekend.
He is the highest-ranked 2022 prospect already off the board and the second ESPN 25 prospect to announce his commitment. Five-star guard Jalen Hood-Schifino committed to Pittsburgh in late December.