William Joseph Cary (born March 22, 1865) was a Republican member of the United States House of Representatives from Wisconsin. He represented Wisconsin’s 4th Congressional District and served six terms in Congress. Cary first entered the House on December 2, 1907, and remained in office until March 3, 1919, participating in the national legislative process during the early twentieth century.

During his tenure, Cary served as a Representative for Wisconsin under the Republican Party label. His congressional service spanned from the 60th through the 65th Congresses, reflecting sustained support from his constituents in the 4th District. While specific committee assignments, legislative initiatives, and post-congressional activities are not detailed in the available record, his twelve years in office mark him as a significant historical member of Congress from Wisconsin.