Judith Winsor Smith (née McLauthlin; November 26, 1821 – December 12, 1921) was an American women's suffrage activist, social reformer, and abolitionist. She was involved in the suffrage movement until the Nineteenth Amendment was passed in 1920, when she voted for the first time at the age of 99. She was a founder and the first president of the , one of the first women's clubs in Massachusetts.