NNT could refer to:
- Nan Airport, Thailand; IATA airport code NNT
- The Nakai–Nam Theun National Biodiversity Conservation Area in Laos
- Nassim Nicholas Taleb
- Number needed to treat, an epidemiological measure
- Nunthorpe railway station, England; National Rail station code NNT
- NAD(P) transhydrogenase, a human mitochondria|mitochondrial enzyme encoded by the NNT gene