Rory John McEwen (born 24 September 1948), Australian politician, was the independent member for the seats of Gordon (1997–2002) and Mount Gambier (2002–2010) in the South Australian House of Assembly.
Before entering politics McEwen had been a TAFE Teacher/Administrator and much experience in local government including Chair of the Grant Council, Chair of the South-East Local Government Association, and Chair of the Greater Green Triangle Regional Development Association.
At the 1997 election, when Liberal Party member for Mount Gambier Harold Allison retired, it was widely expected that McEwen would win the Liberal preselection for the seat. McEwen had also received positive write-ups by The Advertiser as an "experienced political operative." However, in a major upset, he lost to Scott Dixon, a self-employed sawmiller from Mount Gambier. McEwen ran as an independent and just nosed out the Labor candidate for second place. On the final count, a large flow of Labor preferences allowed him to sneak ahead of Dixon by 0.1 percent—a margin of just 53 votes—to win the seat. The election saw him and two other conservative independents holding the balance of power in the newly elected House of Assembly. McEwen made a formal pledge to support the Liberals on matters of confidence and supply, allowing John Olsen another term as premier.
McEwen was comfortably re-elected in the 2002 election. He was initially highly critical of former Liberal Peter Lewis's support of a Labor minority government under Mike Rann. But later, McEwen struck a deal of his own with Labor when he accepted a specially created fourteenth cabinet post in November 2002, at various times being the Minister for Local Government, Forests, Industry, Trade, Regional Development, Small Business, Agriculture, and Food and Fisheries, with a promise that he would retain a cabinet position after the 2006 election.