| Iwadeyama Castle | |
| Nativename-A: | Japanese: 岩出山城 |
| Location: | Miyagi Prefecture, Japan |
| Type: | Mountaintop style castle |
| Controlledby: | Ujiie clan, Date clan |
| Condition: | ruins |
| Built: | 14c or early 15c |
| Builder: | Ujiie Naomasu |
| Materials: | Eathworks |
| Demolished: | 1868 |
| Past Commanders: | Date Masamune |
| Map Type: | Japan Miyagi Prefecture#Japan |
| Map Relief: | 1 |
was a castle in Ōsaki, Miyagi Prefecture, Japan.[1] After serving Hideyoshi for a time, Date Masamune was given Iwatesawa castle and the surrounding lands as his home domain. Masamune moved there in 1591, rebuilt the castle, renamed it Iwadeyama, and encouraged the growth of a town at its base. Masamune stayed at Iwadeyama for 13 years and turned the region into a major political and economic center.[2]
After the Meiji revolution, all the remaining structures of the castle were removed or destroyed.