Robert William Macaulay (May 25, 1921 – August 17, 2010) was a Canadian politician.
Robert William Macaulay was first elected to the Legislative Assembly of Ontario as the Progressive Conservative Member of Provincial Parliament (MPP) for the Toronto riding of Riverdale in the 1951 Ontario election. In 1958, Premier of Ontario Leslie Frost appointed him to cabinet as minister without portfolio and promoted him to Minister of Energy Resources in 1959.
When Frost retired, Macaulay ran to succeed him in the 1961 Progressive Conservative leadership convention finishing third on the fifth ballot. The victor, John Robarts, made Macaulay his Minister of Economics and Development. Macaulay retained his seat in the 1963 Ontario election, but was dropped from cabinet shortly afterwards. He remained in the legislature until May 1964 when he resigned his seat and returned to private life.