Nearly 70 firefighters have been on the scene at Wingfield Recycling Depot on Johansson Road since about 11.30am.
People were working inside when the fire broke out but they all escaped uninjured.
Smoke has been billowing out of the factory since it began, partially caused by plastic burning alongside the cardboard.
There is no threat to neighbouring businesses.
YCA Recycling has been contacted for comment by 9News.
An investigation into the cause of the fire is ongoing.
