Catherine Seppala (1907 – July 4, 1975) was a politician in Ontario, Canada.

She served on Fort William city council from 1953 to 1958.During her time as mayor, the Neebing River Conservation project was initiated and the Westmount Hospital was built.

[1] Also during Seppala's term as mayor, she pressured a local bookseller to remove Lady Chatterley's Lover from his shelves (and more than 700 copies of the books were burned).

[2] In January 1956, as chairman of the city carnival committee, Seppala banned bathing suits from the Fort William carnival queen contest in favour of skating skirts and sweaters.

[3] Seppala was involved in a number of local volunteer organizations, including the Red Cross.