1918 U.S. National Championships – Women's singles

Molla Bjurstedt defeated Eleanor Goss 6–4, 6–3 in the challenge round to win the women's singles tennis title at the 1918 U.S. National Championships. The event was played on outdoor grass courts and held at the Philadelphia Cricket Club in Chestnut Hill, Philadelphia in the United States from June 17 through June 22, 1918. It was the last edition of the event with a challenge round.