The company said Wednesday it plans to close the Schiller Park bakery in October.
According to the Chicago Sun-Times, Hostess Brands CEO Bill Toler said the company is closing the plant as it tries to improve efficiency.
"While the old Hostess company was in bankruptcy, many competitors took over the shelves and are tenaciously defending their business and thus we must be highly efficient and technologically advanced to compete," he said.
Hostess filed for bankruptcy in 2012.
The plant's employees were stunned by the news, Donald Woods said. He is president of the Bakery, Confectionery, Tobacco workers and Grain Millers International Union Local 1.
"They were working like 12 hours, six days a week, and they were looking for this plant to be a part of their future," he said, adding that the workers voted in May to rejoin the union. They had been told the company planned to keep the plant open long term, he said.
The bakery had just reopened a little over a year ago as Twinkies returned to store shelves after Hostess' bankruptcy.
The spongy, cream-filled snack cake was invented in Schiller Park in 1930 by a bakery manager looking for uses for idle shortcake pans.