Billowing smoke was seen from Ford Engine plant as a fire broke out at the Bridgend site on Monday evening.
Firefighters were at the scene on Monday and South Wales Fire and Rescue Service described the fire as "under control" at 8.20pm.
It is understood the fire was at a compound on the site and not the main building.
Images taken by a local resident show that smoke from the fire could be seen from a far distance.
The Bridgend plant is due to close this year with a loss of 1,700 jobs.
An image posted to South Wales Police Bridgend's Twitter account showed a large amount of smoke billowing through the air as fire fighters tackled the fire.
Several fire engines can be seen and BBC Wales reported that the crews from Bridgend, Porthcawl, Kenfig Hill, Pencoed, New Inn and Whitchurch attended.
A spokeswoman from South Wales Fire and Rescue said: "At approximately 7:41pm on Monday July 27, 2020, we received reports of a fire at a commercial property in Waterton, Bridgend.
"Multiple crews attended the scene and extinguished the fire.
"The incident concluded at approximately 9:45pm."
