In a statement released Friday, the committee gave no details on exactly what it is investigating.
It said only that the matter was "transmitted to the committee by the Office of Congressional Ethics on Aug. 30" and that the committee will announce a course of action on the matter by Jan. 28.
Steve Dutton, a spokesman for the Peoria Republican, told the Chicago Tribune that the ethics review involved super PAC money, but he did not elaborate.
The 31-year-old Schock entered Congress in 2009 as its youngest member. He sits on the House Ways and Means committee and is a deputy Republican whip.
He easily won re-election last month and has been mentioned as a possible gubernatorial candidate.