In an emergency alert, the university said the two injured individuals were transported to hospital and classes and campus operations were cancelled for the rest of the day.
The university's alert said that the gunman opened fire at 10.49am in Constant Hall, the centre of the university's college of business.
Within about an hour of the shooting, ODU declared that there was no longer a threat at the campus.
By midday on Thursday, police vehicles with flashing lights had blocked off streets around the Norfolk campus.
Virginia governor Abigail Spanberger wrote on Facebook that she had spoken with university leadership and was mobilising state support to assist with the situation.
The university serves about 24,000 students, according to the school's website.
It has about 240 degree programs, and is known for its research spending and doctoral programs.
Nearly 30 per cent of its students are military-affiliated, according to the website.
The area is also home to Naval Station Norfolk, the largest naval station in the world.
with AP