The robbery happened shortly after 7 p.m. Wednesday in Building C at the University Commons, the Atlanta Journal-Constitution reported.
Three suspects knocked on a dorm room door and pointed a hand gun in a student's face, police said. The suspects then stole an iPod and cell phones from the four victims.
No injuries were reported.
GSU spokeswoman Andrea Jones said at least one of the suspects was also a student and lived on campus, but not in the dormitory where the robbery took place.
Authorities believe some of the victims and suspects were acquaintances, Jones said.
The names of the victims and the suspects were not reported.