One of Australia's biggest chicken suppliers has been placed into voluntary administration with hundreds of jobs likely to be lost.

Red Lea Chickens was on March 29 placed into voluntary administration, with the company saying on its website its financial position means there's "no alternative" but to wind-down operations.

The message on Red Lea Chickens' website on Tuesday evening.

A meeting was reportedly held by administrators at the Blacktown processing plant on Tuesday where hundreds of employees of the family-owned business - which has been operating since 1957 - learned of their fate.

Zagorca Ciolac says she has been working at the plant for the 33 years.

"It's difficult ... now we have to go look for another job," Ms Ciolac told Network Ten on Tuesday.

Another employee, Suzann Cook said it was "just wrong" and not fair.

The company says on its website its Blacktown plant is "state of the art" with more than 500 employees working there.

"It's the original property where our story began, from our humble beginnings with door to door fresh poultry sales," the website says.

McGrathNicol partners Barry Kogan, Jason Preston and Kathy Sozou have been appointed as administrators.

The NSW branch of the Australasian Meat Industry Employees' Union said it had no comment about the matter at this stage.

Red Lea Chickens has been contacted for comment.

AAP