A female DBA/2 mouse is characterized by the presence of abundant cytoplasmic granules in the renal tubules. In the present study, the morphometrics of kidneys from female DBA/2 mice at 5, 15, 18, 21, and 24 months of age were investigated to determine the age-dependent renal changes in this mouse strain. Glomerular and tubulointerstitial disease progressed with age, and the semiquantitative scores of these lesions showed significant increases. Granules were observed in the proximal straight tubules and no changes were observed in their localization, fine structure, and quantitative scores. It was concluded that the tubular cytoplasmic granules in the female DBA/2 mouse were not affected by age-dependent functional reduction of the kidney.