The daughter of a dentist from Schwabing, she graduated from school with top marks, after which she cared for her seriously ill mother for several years. Elfriede Löhr was one of the most active members in Bavaria of the Jehovah's Witnesses, who were banned by the Nazi regime. From 1936 onwards, she transported Jehovah's Witnesses writings through Germany – mostly at night. In the same year, she traveled illegally to a congress in Switzerland, where a resolution against the persecution of Jehovah's Witnesses was passed, which was distributed as a leaflet throughout Germany on December 12, 1936. Elfriede Löhr also played a key role in another campaign in 1937. “As is now absolutely certain, Löhr prepared and carried out the ‘Open Letter’ leaflet campaign in Bavaria,” wrote the Munich Gestapo.
She was arrested in Berlin on August 21, 1937, held in solitary confinement for several months and subjected to interrogations involving blackmail. But she did not betray her fellow believers. After suffering a nervous breakdown, she was examined for her mental state in the psychiatric ward of Munich's Stadelheim Prison. In 1939, Löhr was sent to the Lichtenburg W's Concentration Camp, then to Ravensbrück Concentration Camp. There she refused to sew ammunition pockets onto soldiers' uniforms, which was punished with starvation rations and weeks of imprisonment in darkness. Thanks to the help of a member of her religious community, a doctor, she survived pneumonia in 1943, which would otherwise have meant certain death in the concentration camp. After almost eight years in prison, she was liberated in 1945.
In 1950, Elfriede Löhr attended a missionary school and then dedicated herself to spreading her religion in Austria. She spent the later years of her life at the German headquarters of the Jehovah's Witnesses in the Taunus region.