Following his excellent work as key keeper for nearby Newcastle, Martin Bryn will now be responsible for both monuments on a daily basis.
As a local resident, Martin will keep the sites free of litter whilst also reporting any damage or vandalism to Cadw and notifying the police of any undesirable person or activities at the sites.
Martin said: "Looking after Newcastle has been a real pleasure and I'm now looking forward to additionally caring for Ogmore.
"Being a local boy, I've always been interested in the history of the area and I enjoy making sure the sites looks presentable whilst also meeting new visitors and helping tourists who like to find out more about Ogmore and Newcastle."
Nestling in the Ewenny estuary, the original earthworks of Ogmore Castle were built by the Normans just after 1100.
The castle was placed in the keeping of William de Londres - a knight with a fierce reputation.
Together with Coity and Newcastle, the Ogmore Castle formed part of a crucial line of defence against the Welsh.
Wayne Evans, Cadw's Visitor Services Manager, said: "We have been very impressed with Martin's work at Newcastle.
"He has taken great pride in caring for the monument and as he lives locally and already has experience looking after Newcastle, Cadw welcomes his appointment as key keeper of Ogmore and hopes he will enjoy this important role."
Martin Bryn talks about his work at Newcastle