DCN may refer to:
- Daily Commercial News, an Australian shipping newspaper first published in 1891
- Decorin, a member of the proteoglycan family proteins
- Deputy Chief of Navy, Australia
- Direction des Constructions Navales, French shipbuilder
- Dorsal cochlear nucleus, a structure located on the brainstem
- Dynamic circuit network, a high performance computer network technology
- Data Communication Network, management network for telecommunication transport systems