Martha Elizabeth Keys (née Ludwig; August 10, 1930 – December 19, 2024) was an American politician who served in the U.S. House of Representatives from Kansas from 1975 to 1979.

She attended Olivet College from 1946 to 1947 and earned a Bachelor of Arts degree at the University of Missouri–Kansas City in 1951.

When Bill Roy retired from the U.S. Congress, her brother-in-law Senator Gary Hart, a Colorado Democrat, persuaded her to run for the seat.

She was elected a Democrat to the United States House of Representatives from Manhattan, Kansas in 1974 and served two terms before being defeated for reelection in 1978.

While serving in the House of Representatives, Keys and her husband divorced, and she was remarried to fellow Congressman Andrew Jacobs Jr.