Moore was born in Columbia, Lancaster County, Pennsylvania, USA, on 28 January 1907. She was the fifth of six children born to parents Mathias A. Teufel (1867–1928) and Ellen J. Gilbert (1872–1915). Her paternal grandparents were born in Germany. Her siblings were Francis, Raymond (1895–1916), Ella Newcomer (1899–1979), John and Gladys. Her mother died of tuberculosis when Miriam was still a young girl, so the siblings moved to their aunt and uncle, Joseph and Mary Denison and their three children. Her sister Ella helped a lot to raise her younger siblings. When she got old enough to work, she became a weaver. She made fabric at the former Schwarzenbach-Huber Silk Mill.

In her youth, she loved to go to dances at church and the Columbia Moose lodge. At one of those dances, she met her future husband, James Edwin Moore (1915–1984). The couple had one son, James Edwin Jr. (1938–2020).

Her husband passed away in 1984. She spent most of her life in Columbia, before moving to the Luther Acres Retirement Community in Lititz. She was a member of St. John’s Lutheran Church where she was in the choir, taught Sunday school, and was a founding member of Meals on Wheels.

Miriam Moore passed away in Lititz, Lancaster County, Pennsylvania, USA on 11 May 2018 at the age of 111 years, 103 days. She was survived by her only son, two grandchildren and five great-grandchildren.