Emergency responders were not able to revive Alyssa Olafson, 19, after being called to her fifth-floor room at about 1:20 a.m.
WMU officials said there is no indication that drugs or alcohol were involved; they believe a pre-existing medical condition may have been a factor in her death.
The exact cause of death may not be known for several weeks.
Olafson was a freshman at WMU, and a pre-health and human services major who made the dean's list her first semester on campus this past fall, according to the school. She was a 2013 graduate of Allendale High School.
The school has counselors on site to work with students and hall personnel.