The Cook County, Illinois general election was held on November 3, 1998. Primaries were held March 17, 1998. Elections were held for Assessor, Clerk, Sheriff, Treasurer, President of the Cook County Board of Commissioners, all 17 seats of the Cook County Board of Commissioners, all 3 seats of the Cook County Board of Review, 4 seats on the Water Reclamation District Board, and judgeships on the Circuit Court of Cook County.