JoAnne L. Buth (born May 23, 1954) is a former Canadian politician. She was appointed to the Canadian Senate by Stephen Harper on January 6, 2012 (replacing the retired Sharon Carstairs) and sat as a Conservative representing Manitoba. She retired from the Senate on August 10, 2014 in order to become CEO of the Canadian International Grains Institute, a group that promotes Canadian field crops.
She has a B.Sc. in biology from the University of Winnipeg and an M.Sc. in entomology from the University of Manitoba.
Buth's background in agriculture includes stints as a research and development manager with DowElanco Canada and as an information officer for the federal agriculture department's research station in Winnipeg. More recently she worked in Carman, Manitoba as a manager and weed management specialist in Manitoba's provincial ministry of agriculture. Prior to her Senate appointment, she was president of the Canola Council of Canada, a lobby group for the canola industry.