John Duncan MacEachern (born 1946) is a former educator and political figure in Nova Scotia, Canada. He represented Cape Breton East in the Nova Scotia House of Assembly as a Liberal member.He was born in Glace Bay, Nova Scotia and was educated at Saint Francis Xavier University and Dalhousie University. MacEachern was a math and physics teacher and high school vice-principal. He served in the province's Executive Council as Minister of Education and Culture and Minister of Community Services.