NUP is an abbreviation for:
- National Union Party (disambiguation), a number political parties in various states
- Neapolis University, Pafos, a university in Cyprus
- Necrotizing ulcerative periodontitis, a subclassification of Necrotizing periodontal diseases
- New Union Party, a political party in the United States
- New Unity Partnership, a trade union in the United States
- Nottingham University Press
- Northwestern University Press
- Nuclear Pore