Sir William Wilfred Sullivan (December 6, 1839 – September 30, 1920) was a Prince Edward Island journalist, politician and jurist, the fourth premier of Prince Edward Island. A native of Hope River, Sullivan had a career as an assistant editor at the Charlottetown Herald as well as a lawyer before being elected to the provincial legislature in 1872 as a Liberal MLA. In 1889, Sullivan was appointed Chief Justice of PEI and served in that position until his retirement in 1917. In 1914 he was made a Knight Bachelor by King George V.