Mark Armstrong (born February 21, 2004) is an American professional basketball player for the Long Island Nets of the NBA G League.

[2] He averaged 14.1 points, 2.4 rebounds, 2.7 assists, and 2.2 steals in eleven games during his junior season, which was shortened due to the COVID-19 pandemic.

[3] Armstrong was named the Hudson County Interscholastic League Player the Year as a senior after averaging 23.4 points, five rebounds, and 2.8 assists per game.

[5] On April 8, 2021, he committed to playing college basketball for Villanova over offers from Auburn, UConn, Louisville, Seton Hall, Rutgers, Stanford, and Kansas.

[8] He was named the Big East Conference Freshman of the Week after scoring 10 points on 3-of-4 shooting from the field in his first career start against Oklahoma.