Ruth Bietenhard, née Lehmann (11 January 1920 in Bern – 19 February 2015 in Thun), was a Swiss author and teacher.
After studying Romance languages and literature in Bern, Geneva and Paris, she obtained a grammar school teaching diploma in French, Italian and Latin in Bern in 1945 and completed her doctorate in Romance languages and literature here in 1949 with the dissertation Le sémantisme des mots expressifs en Suisse Romande.
She later wrote specialised articles and had a column on language and dialect for the newspaper Der Bund until 2003.
She actively supported her husband until 1969 in building up the Sonnenfeld-Schwäbis parish, which was directly adjacent to the town of Thun.
As a conservative woman, she belonged politically to the SVP, although she was also interested in feminist theology.