The 1905 U.S. Open was the 11th U.S. Open, held September 21–22 at Myopia Hunt Club in South Hamilton, Massachusetts, northeast of Boston. Willie Anderson won his third consecutive U.S. Open title, and his record fourth overall, two strokes ahead of runner-up Alex Smith.
Smith led Anderson by a shot heading to the final round, but a third consecutive round of 80 dropped him back to 2nd place. Anderson closed with rounds of 76 and 77 to post a 314 total, two-strokes ahead of Smith. Scoring conditions at Myopia were so difficult that no player broke 75 in any round.
Anderson's feat of three consecutive U.S. Open titles remains unmatched in tournament history, while his 4 wins has been equaled by only Bobby Jones, Ben Hogan, and Jack Nicklaus.