Delyn can refer to:
- Delyn (district), a former district of Wales
- Delyn (UK Parliament constituency), a constituency based on the district
- Delyn (National Assembly for Wales constituency), a constituency based on the district
Delyn is a constituency of the House of Commons of the Parliament of the United Kingdom, first used in the 1983 General Election. It elects one Member of Parliament (MP) by the first past the post system of election.
The Delyn Welsh Assembly constituency was created with the same boundaries in 1999.