Ian Gilfillan (born 7 June 1932) is a former Australian politician.
He was educated in Adelaide and was based on Kangaroo Island.
He contested the 1974 federal election as a member of the Australia Party, but joined the Australian Democrats in 1977.
In 1982, he was elected to the South Australian Legislative Council as a Democrat, holding the position until 1993.
He returned to the Council in 1997 and served until his retirement in 2006.