The Student Union is centrally located on campus and serves as a key facility that houses numerous services, including the OSUIT Cafeteria, Bookstore, Post Office, and Campus Health Services. It provides various seating and meeting areas for students, such as the PSO Lounge for meeting in-between classes or alternative eating, and the Viersen and ONG Lounges for quiet study or conversation. Additionally, the Student Union features the Veterans Lounge, which is a dedicated quiet space for the institution's veteran students to eat, study, or relax.