Renal parenchymal infection or Pyelonephritis, constituted 1% to 4% among pregnancies. It is a condition in which the renal tubules become inflamed and their ability to reabsorb sodium is greatly affected. Aim of study; the aim of study was to study the effect of Pyelonephritis during pregnancy on mother's quality of Life. Methods: Study design: descriptive study. Setting: The study was conducted at outpatient of obstetric department Menoufia University and second setting was Ministry of health Teaching hospital. Subjects: The subjects of this study were 120 pregnant mothers medically diagnosed with pyelonephritis chosen according to the inclusion criteria. Pregnant mothers without any complications rather than pyelonephritis. Type of sample: A convenient sample was utilized from both study setting.