Police believe the shooter is a former student who was one of the three injured early Sunday, spokeswoman Yuri Rodgers Milligan said.
A night manager for the Harkness Hall dorm at the school in southeastern Virginia was also hurt. The third victim was not identified but was not a student.
Milligan said all three are alive but she did not know their conditions. Officials did not know the shooter's motive.
Per university policy, all students, faculty and staff were notified about the situation via text message and e-mail.
The school remained on lockdown Sunday morning while police investigated.
Hampton University is a private school with about 5,700 students. It was founded in 1868 during Reconstruction to educate black leaders for the newly freed slaves.