The 6-foot-8 center is the 36th-ranked prospect on the ESPN 100 for 2020 and the Spartans' second commitment from that list after point guard Jalen Terry.
"Michigan State is a great school and the basketball staff is amazing," Sissoko told ESPN's Jeff Borzello and Paul Biancardi. "Coach (Tom) Izzo is such a humble and honest person. I know he can help me become a better player. Every time I speak with Coach Izzo, he always keeps it real."
Sissoko averaged 12.5 points and 8.9 rebounds per game during his junior year but will miss a portion of the upcoming high school season with a broken hand.
The Mali native has been highly touted for his athleticism and relentless motor.
Kansas, Memphis, and BYU were the other finalists for Sissoko.