Qalay Sherwana stands atop a hill outside the city of Kalar in Garmian.
For years it has been a major landmark and houses a museum that displays the history of Garmian.
Shukur Mohammd, head of Garmiyan Heritage Department said most of the damage has been done to "the third floor's dome, but in general, 35 percent of the Castle has been damaged."
He said they were working to file a complete assessment of the damages in order to start repair work "as soon as possible."
The Sherwana Castle was rebuilt on the original site that dates back to 1734.

At least seven people were killed in Kalar, Darbandikhan and Sulaimani in Sunday night's earthquake, local officials said, and more than 300 hospitalized for injuries.
The epicenter of the earthquake was near the town of Halabja near the Iranian border.
