Kastelli Giant's Church (Finnish: Kastellin jätinkirkko) is a prehistoric stone enclosure situated near Pattijoki in the North Ostrobothnia region of Finland.

It is one of the largest of forty such "Giant's Churches" to be found in this region of Finland.

The Giant's Church at Kastelli is a rectangular stone enclosure measuring around 60 by 35 metres.

[2] The enclosure is surrounded by more than twenty stone cairns.

[2] Holes found in the area may have been for the storing of killed animals.