The fire started shortly after 6 a.m. near 65th Street and Archer Avenue in Bedford Park.
The plant is called Ingredion; it is a food ingredient manufacturing company, a spokesperson said.
One employee was injured but is expected to be released from the hospital soon, according to a company spokesperson.
According to a company spokesperson, the fire was mechanical.
Bedford Park officials said the fire was contained to the factory. The fire was out by 9:30 a.m.
Video shows as workers stood outside as crews worked on the fire.
No traffic was impacted.
It is unknown what caused the fire.