On 4 December 2011, Tereshkova was elected to the State Duma, the lower house of the Russian legislature, as a representative of the Yaroslavl Oblast and a member of the United Russia party. In the 6th State Duma, together with Yelena Mizulina, Irina Yarovaya and Andrey Skoch, she was a member of the inter-factional committee for the protection of Christian values. In this capacity, she supported the introduction of amendments to the preamble of Constitution of Russia, to add that "Orthodoxy is the basis of Russia's national and cultural identity".