Rooney, 90, has obtained a restraining order against his stepson and stepdaughter, claiming they emotionally abused him for years and took over his finances.
"You can't believe that it's happening to you," CNN quoted Rooney as telling the committee. "You feel overwhelmed."
During the hearing, Rooney suggested Congress pass a law to make the abuse of seniors at the hands of family members and caregivers a specific crime.
"I'm asking you to stop this elderly abuse. I mean to stop it. Now. Not tomorrow, not next month, but now," he said.
Rooney's film credits include "Boys Town," "Babes in Arms," the Andy Hardy film series, "Breakfast at Tiffany's" and "Night at the Museum."
He received a special Academy Award in 1938 and an honorary award in 1982, and was nominated for five acting Oscars.
A five-time Emmy nominee, Rooney won the television prize in 1982 for his performance in "Bill," as a mentally challenged man making his way into the world for the first time.