Gordon studied at Mount Holyoke Female Seminary (now Mount Holyoke College) in South Hadley, Massachusetts, and at Lasell Seminary in Auburndale, Massachusetts. In 1877, at a Boston revival meeting held by evangelist Dwight L. Moody (Moody, Dwight L), she met Frances Willard (Willard, Frances), and within a short time she had become Willard's private secretary. She took up residence with her in Evanston, Illinois, and in 1879 she followed her friend and employer into the work of the Woman's Christian Temperance Union (WCTU). Gordon traveled throughout the country for a number of years, lecturing and organizing local branches and children's auxiliaries of the WCTU. She was particularly interested in the organization's appeal to children through the Loyal Temperance Union, for which she wrote a number of marching songs. She became superintendent of juvenile work for the new World Woman's Christian Temperance Union in 1891.

On the death of Willard in 1898, Gordon became vice president of the national WCTU under Lillian M.N. Stevens. Gordon published The Beautiful Life of Frances E. Willard in 1898 and What Frances E. Willard Said in 1905. In addition to founding the Young Campaigners for Prohibition (1910), she succeeded Stevens as president (1914) of the WCTU and promptly focused the organization on the campaign for a federal prohibition amendment. During World War I she was instrumental in persuading President Woodrow Wilson to take various steps short of outright prohibition, such as prohibiting the use of foodstuffs for the manufacture of alcoholic beverages, and with the ratification of the Eighteenth Amendment in January 1919 she urged the WCTU to become interested in enforcement. She also turned the organization's attention to other causes, including Americanization of immigrants, child welfare, and the condition of women in industry.

Having been elected president of the World WCTU in 1922, Gordon resigned the presidency of the national WCTU in 1925 to devote her time to the world organization. Other books by her include Toots and Other Stories (1906), White Ribbon Hymnal (1911), Young People's Temperance Chorus Book (1911), What Lillian M.N. Stevens Said (1914), Marching Songs for Young Crusaders (1916), Jubilee Songs (1923), and Everybody Sing (1924).