Ruth Ann Jamnick (born November 8, 1941) was a Democratic member of the Michigan House of Representatives. Prior to her election to the House, Jamnick served 22 years as the Ypsilanti Township Treasurer, and she served one term as that township's supervisor following her time in the House.
Jamnick also served as a member of the State Boundary Commission from 2005 to 2013. She was also a member of the Washtenaw County chapter of the Michigan Townships Association and as the association's second vice president. Jamnick was the Ypsilanti Township delegate to the Southeast Michigan Council of Governments (SEMCOG), and is a past chair of the Washtenaw County United Way.