Republican Randy Hultgren called the battle for the lab's budget "a fight for the future of science in the U.S."
The lab houses the second largest particle accelerator in the world.
A spokesperson says congress is considering cuts as high as 40 percent of its $400-million annual budget, which would result in a layoff of a quarter of its 1,900 employees.
"We need to keep this vital work going, and that's my hope that as we go through this budget process - it's a painful time, but that we can do it in a way that doesn't destroy the good work that's happening and destroy our future," said Hultgren.
The cuts would also result in major salary reductions for those who keep their jobs.