| Past champions | |||
| Year | Winner | Score | Course |
| 1999 | Tiger Woods | 273 (15-under) | Cog Hill G&CC, Lemont, Ill. |
| 1998 | Joe Durant | 271 (17-under) | Cog Hill G&CC, Lemont, Ill. |
| 1997 | Tiger Woods | 275 (13-under) | Cog Hill G&CC, Lemont, Ill. |
| 1996 | Steve Stricker | 270 (18-under) | Cog Hill G&CC, Lemont, Ill. |
| 1995 | Billy Mayfair | 279 (9-under) | Cog Hill G&CC, Lemont, Ill. |
| 1994 | Nick Price | 277 (11-under) | Cog Hill G&CC, Lemont, Ill. |
| 1993 | Nick Price | 269 (19-under) | Cog Hill G&CC, Lemont, Ill. |
| 1992 | Ben Crenshaw | 276 (12-under) | Cog Hill G&CC, Lemont, Ill. |
| 1991 | Russ Cochran | 275 (13-under) | Cog Hill G&CC, Lemont, Ill. |
| 1990 | Wayne Levi | 275 (13-under) | Butler National GC, Oak Brook, Ill. |
| 1989 | x-Mark McCumber | 275 (13-under) | Butler National GC, Oak Brook, Ill. |
| 1988 | Jim Benepe | 278 (10-under) | Butler National GC, Oak Brook, Ill. |
| 1987 | y-D.A. Weibring | 207 (9-under) | Butler National GC, Oak Brook, Ill. |
| 1986 | x-Tom Kite | 286 (2-under) | Butler National GC, Oak Brook, Ill. |
| 1985 | xa-Scott Verplank | 279 (9-under) | Butler National GC, Oak Brook, Ill. |
| 1984 | x-Tom Watson | 280 (8-under) | Butler National GC, Oak Brook, Ill. |
| 1983 | Mark McCumber | 284 (4-under) | Butler National GC, Oak Brook, Ill. |
| 1982 | Tom Weiskopf | 276 (12-under) | Butler National GC, Oak Brook, Ill. |
| 1981 | Ed Fiori | 277 (11-under) | Butler National GC, Oak Brook, Ill. |
| 1980 | Scott Simpson | 281 (7-under) | Butler National GC, Oak Brook, Ill. |
| 1979 | x-Larry Nelson | 286 (2-under) | Butler National GC, Oak Brook, Ill. |
| 1978 | x-Andy Bean | 282 (6-under) | Butler National GC, Oak Brook, Ill. |
| 1977 | Tom Watson | 283 (5-under) | Butler National GC, Oak Brook, Ill. |
| 1976 | Al Geiberger | 288 (4-over) | Butler National GC, Oak Brook, Ill. |
| 1975 | Hale Irwin | 283 (1-under) | Butler National GC, Oak Brook, Ill. |
| 1974 | Tom Watson | 287 (3-over) | Butler National GC, Oak Brook, Ill. |
| 1973 | Billy Casper | 272 (12-under) | Midlothian CC, Midlothian, Ill. |
| 1972 | Jim Jamieson | 271 (13-under) | Sunset Ridge, Winnetka, Ill. |
| 1971 | Bruce Crampton | 279 (5-under) | Olympia Fields CC, Olympia Fields, Ill. |
| 1970 | Hugh Royer | 273 (11-under) | Beverly CC, Chicago |
| 1969 | Billy Casper | 276 (8-under) | Midlothian CC, Midlothian, Ill. |
| 1968 | Jack Nicklaus | 273 (11-under) | Olympia Fields CC, Olympia Fields, Ill. |
| 1967 | Jack Nicklaus | 274 (10-under) | Beverly CC, Chicago |
| 1966 | Billy Casper | 283 (1-under) | Medinah CC, Medinah, Ill. |
| 1965 | Billy Casper | 270 (14-under) | Tam O'Shanter CC, Niles, Ill. |
| 1964 | Chi Chi Rodriguez | 268 (16-under) | Tam O'Shanter CC, Niles, Ill. |
| 1963 | x-Arnold Palmer | 280 (4-under) | Beverly CC, Chicago |
| 1962 | Jacky Cupit | 281 (3-under) | Medinah CC, Medinah, Ill. |
| 1961 | Arnold Palmer | 271 (13-under) | Blythefield CC, Grand Rapids, Mich. |
| 1960 | x-Stan Leonard | 278 (10-under) | Western G&CC, Detroit |
| 1959 | Mike Souchak | 272 (12-under) | Pittsburgh Field Club, Fox Chapel, Pa. |
| 1958 | Doug Sanders | 275 (13-under) | Red Run GC, Royal Oak, Mich. |
| 1957 | x-Doug Ford | 279 (9-under) | Plum Hollow GC, Detroit, Mich. |
| 1956 | x-Mike Fetchick | 284 (4-under) | Presidio GC, San Francisco |
| 1955 | Cary Middlecoff | 272 (16-under) | Portland GC, Portland, Ore. |
| 1954 | x-Lloyd Mangrum | 277 (11-under) | Kenwood CC, Cincinnati |
| 1953 | Dutch Harrison | 278 (6-under) | Bellerive CC, St. Louis |
| 1952 | Lloyd Mangrum | 274 (14-under) | Westwood CC, St. Louis |
| 1951 | Marty Furgol | 270 (14-under) | Davenport CC, Davenport, Iowa |
| 1950 | Sam Snead | 282 (6-under) | Brentwood CC, Los Angeles |
| 1949 | Sam Snead | 268 (20-under) | Pittsburgh Field Club, Fox Chapel, Pa. |
| 1948 | x-Ben Hogan | 281 (7-under) | Brookfield CC, Buffalo, N.Y. |
| 1947 | John Palmer | 270 (18-under) | Salt Lake City CC, Salt Lake City, Utah |
| 1946 | Ben Hogan | 271 (17-under) | Sunset CC, St. Louis |
| 1945 | No tournament | ||
| 1944 | No tournament | ||
| 1943 | No tournament | ||
| 1942 | Herman Barron | 276 (8-under) | Phoenix GC, Phoenix, Ariz. |
| 1941 | Ed Oliver | 275 (9-under) | Phoenix GC, Phoenix, Ariz. |
| 1940 | x-Jimmy Demerat | 293 (5-over) | River Oaks CC, Houston |
| 1939 | Byron Nelson | 281 (3-under) | Medinah CC, Medinah, Ill. |
| 1938 | Ralph Guldahl | 279 (9-under) | Westwood CC, St. Louis |
| 1937 | x-Ralph Guldahl | 288 (Even) | Canterbury CC, Cleveland, Ohio |
| 1936 | Ralph Guldahl | 274 (10-under) | Davenport CC, Davenport, Iowa |
| 1935 | John Revolta | 290 (6-over) | South Bend CC, South Bend, Ind. |
| 1934 | x-Harry Cooper | 274 (6-under) | CC of Peoria, Peoria, Ill. |
| 1933 | Mac Smith | 282 (2-under) | Olympia Fields CC, Olympia Fields, Ill. |
| 1932 | Walter Hagen | 287 (1-under) | Canterbury GC, Cleveland, Ohio |
| 1931 | Ed Dudley | 280 (4-under) | Miami Valley GC, Dayton, Ohio |
| 1930 | Gene Sarazen | 278 (N/A) | Indianwood G&CC, Detroit |
| 1929 | Tommy Armour | 273 (7-under) | Ozaukee CC, Milwaukee, Wis. |
| 1928 | Abe Espinosa | 291 (3-over) | North Shore GC, Chicago |
| 1927 | Walter Hagen | 281 (3-under) | Olympia Fields CC, Olympia Fields, Ill. |
| 1926 | Walter Hagen | 279 (1-under) | Highland G&CC, Indianapolis, Ind. |
| 1925 | Mac Smith | 281 (3-under) | Youngstown CC, Youngstown, Ohio |
| 1924 | Bill Mehlhorn | 293 (5-over) | Calumet CC, Chicago |
| 1923 | Jock Hutchison | 281 (1-over) | Colonial CC, Memphis, Tenn. |
| 1922 | Mike Brady | 291 (3-over) | Oakland Hills CC, Detroit |
| 1921 | Walter Hagen | 287 (3-over) | Oakwood Club, Cleveland, Ohio |
| 1920 | Jock Hutchison | 296 (12-over) | Olympia Fields CC, Olympia Fields, Ill. |
| 1919 | Jim Barnes | 283 (5-under) | Mayfield CC, Cleveland, Ohio |
| 1918 | No tournament | ||
| 1917 | Jim Barnes | 283 (5-under) | Westmoreland CC, Chicago |
| 1916 | Walter Hagen | 286 (N/A) | Blue Mound CC, Chicago |
| 1915 | Tom McNamara | 304 (16-over) | Glen Oak CC, Chicago |
| 1914 | Jim Barnes | 293 (1-over) | Interlachen CC, Minneapolis, Minn. |
| 1913 | John McDermott | 295 (15-over) | Memphis CC, Memphis, Tenn. |
| 1912 | Mac Smith | 299 (11-over) | Idlewild CC, Chicago |
| 1911 | Robert Simpson | 2&1 | Kent CC, Grand Rapids, Mich. |
| 1910 | a-Charles Evans Jr. | 6&5 | Beverly CC, Chicago |
| 1909 | Willie Anderson | 288 (Even) | Skokie CC, Chicago |
| 1908 | Willie Anderson | 299 (15-over) | Normandie GC, St. Louis |
| 1907 | Robert Simpson | 307 (23-over) | Hinsdale GC, Hinsdale, Ill. |
| 1906 | Alex Smith | 306 (26-under) | Homewood CC, Chicago |
| 1905 | Arthur Smith | 278 (6-under) | Cincinnati GC, Cincinnati, Ohio |
| 1904 | Willie Anderson | 304 (20-over) | Kent CC, Grand Rapids, Mich. |
| 1903 | Alex Smith | 318 (30-over) | Milwaukee CC, Milwaukee, Wis. |
| 1902 | Willie Anderson | 299 (N/A) | Euclid Club, Cleveland, Ohio |
| 1901 | Laurie Auchterlonie | 160 (18-over) | Midlothian CC, Chicago |
| 1900 | No tournament | ||
| 1899 | x-Willie Smith | 156 (12-over) | Glen View GC, Chicago |
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