The station was damaged by the 2011 Tōhoku earthquake and tsunami; however services have now been replaced by a provisional bus rapid transit line.

Ōya-Kaigan Station had one side platform serving a single bi-directional track.

The station was absorbed into the JR East network upon the privatization of the Japan National Railways (JNR) on April 1, 1987.

The 2011 Tōhoku earthquake and tsunami severely damaged he station and nearby tracks, and rail services have now been replaced by a bus rapid transit line.

Media related to Oya-Kaigan Station at Wikimedia Commons (Stations in italics were formerly on the section destroyed by the 2011 Tōhoku earthquake and tsunami and are currently served by a Bus Rapid Transit line.)