WNIU (90.5 FM) is a public radio station licensed to Northern Illinois University in DeKalb, Illinois, United States. It is part of Northern Public Radio along with WNIJ. It primarily features classical music programming. WNIU broadcasts in the hybrid digital HD format.

Established in 1954, WNIU serves the Northern Illinois region. It provides a diverse range of programming to its listeners, including live classical performances, interviews with musicians, and coverage of local arts and cultural events.

42°00′54″N 89°00′07″W / 42.015°N 89.002°W / 42.015; -89.002