The junior guard made the announcement on social media after his first practice with the Knights on Wednesday.
He played his first two high school seasons at Sierra Canyon High School with his older brother, Bronny James.
Bryce James previously was set to transfer to Campbell Hall in Studio City, California, but reconsidered.
Already on the Notre Dame roster is Mercy Miller, son of rapper Master P. Miller is a four-star prospect who committed to Houston’s 2024 class two years ago.
The 247Sports composite lists James as the No. 14 shooting guard in the 2025 class.