Tromøy Church (Norwegian: Tromøy kirke) is a medieval parish church of the Church of Norway located on the island of Tromøy in Arendal Municipality, Agder county, Norway. It is situated on the southern side of the island, overlooking the Skagerrak strait. The church is part of the Tromøy parish within the Arendal prosti (deanery) in the Diocese of Agder og Telemark.
The structure was originally built around the year 1150 as a Romanesque stone church. In its initial form, it was a rectangular long church. Between 1748 and 1758, the building underwent a significant transformation and was expanded into a cruciform design. This renovation involved the removal of the original medieval choir and the addition of two timber-framed transepts to create the cross-shaped layout.
Due to its prominent location near the coastline, the church historically served as a vital seamark for maritime navigation. The exterior consists of whitewashed stone and timber, while the interior features a Baroque-style altarpiece and pulpit dating from the 1720s. The church also houses a medieval baptismal font carved from soapstone.
Tromøy Church is a protected cultural heritage site. It currently has a seating capacity of approximately 290 people and remains an active place of worship for the local community.