Marion Military Institute had a total enrollment of 332 students in 2024. The full-time enrollment at Marion Military Institute is 329 students and the part-time enrollment is 3. This means that 99.1% of students enrolled at Marion Military Institute are enrolled full-time.

The enrolled student population at Marion Military Institute, both undergraduate and graduate, is 50.3% White, 27.4% Black or African American, 13.3% Hispanic or Latino, 6.33% Two or More Races, 1.81% Asian, 0.602% Native Hawaiian or Other Pacific Islanders, and 0.301% American Indian or Alaska Native.

Students enrolled at Marion Military Institute in full-time Undergraduate programs are most commonly White Male (38.3%), followed by Black or African American Male (19%) and White Female (13.8%).