This Romanesque church in the style of the Compostela School from the 12th century, is nestled inside the Ciudad Vieja. It is considered to be the oldest church in A Coruña. It has Gothic elements from the 14th and 15th centuries and reconstructions from different periods due to having suffered several fires. The main doorway has a Gothic rose window from the end of the 14th century, and the tympanum has a representation of more recent Saint James the Apostle. On the north doorway is the tympanum with the "Agnus Dei". Inside there are ancient tombs and a stone pulpit from the 17th century. Interesting Roman altars have been found inside the temple.

Particularly noteworthy are the images of the Virgin and Child, the Virgin of the Milk and Saint James the Apostle. The City Council used to hold meetings in the atrium of the church in the 14th century, and one of its towers (nowadays only the bell tower remains) held gunpowder for the defence of the city. The church was originally dedicated to pilgrims who came to Compostela by sea.

The Church of Santiago has been listed as a Cultural Heritage Site since 1972.