Donaghadee (from Irish: Domhnach Daoi, meaning "Daoi's church") is a small town in County Down, Northern Ireland. It lies on the northeast coast of the Ards Peninsula, about 18 miles (29 km) east of Belfast and about six miles (10 km) south east of Bangor. It is in the civil parish of Donaghadee and the historic barony of Ards Lower. It had a population of 6,869 people in the 2011 Census.
In the 17th century Ulster ports began to rise in prominence. In 1625 William Pitt was appointed as Customer of the ports of Newcastle, Dundrum, Killough, Portaferry, Donaghadee, Bangor and Holywood. In 1637 the Surveyor General of Customs issued a report compiled from accounts of customs due from each port and their "subsidiary creeks". Of the Ulster ports on the list, Carrickfergus was first, followed by Bangor, Donaghadee and Strangford.
The town also featured in the Irish Rebellion of 1798. On the morning of Pike Sunday, 10 June 1798 a force of United Irishmen, mainly from Bangor, Donaghadee, Greyabbey and Ballywalter attempted to occupy the town of Newtownards. They met with musket fire from the market house and were defeated.