William Frazer Baker (1866 – December 4, 1930) was the owner of the Philadelphia Phillies of the National League from 1913 through 1930. Baker was appointed New York City Police Commissioner in July 1909 by Mayor George B. McClellan, Jr. During his brief tenure, he was accused of interfering in gambling investigations. He resigned from his position in October 1910. In January 1913, Baker was part of a group led by his nephew, William Locke, that purchased the club. Baker was elected Team President in October 1913, following the death of Locke earlier in the year. He was at the helm two years later when the Phillies played in the 1915 World Series.