Lettie D. Campbell was an American politician from Afton, Wyoming, who served a single term in the Wyoming House of Representatives. She was elected in 1930, and represented Lincoln County from 1931 to 1933 as a Republican in the 21st Wyoming Legislature. Campbell represented Lincoln County alongside R. H. Embree, A. E. Wilde, and Platt Wilson.
Campbell had a brother named C. J. Dewey.