Josephine Elizabeth Tilden (March 24, 1869 – May 15, 1957) was an American expert on pacific algae. She was the first woman scientist employed by the University of Minnesota. Tilden established a research station in British Columbia which lasted only until 1906. When Tilden became an assistant Professor in 1903, she was the first female scientist employed by the University of Minnesota. In 1910, despite not having a doctorate, Tilden was promoted to full professor.