Diabetic Bladder Dysfunction (DBD) is a common complication of diabetes mellitus (DM) with poorly understood natural history. This study examined the temporal changes in bladder function 3, 9, 12 and 20 weeks after induction of DM by streptozotocin (STZ) in male C57BL/6 mice, in comparison to age-matched diabetic mice treated with insulin, 5% sucrose-induced diuretic mice and sham-treated control mice. Conscious cystometrograms (CMG) of mice were examined in addition to the measurements of micturition cycle. Diabetes resulted in decreased body weight. Bladder weight, urine output, bladder capacity and compliance increased in the DM and diuretic groups. Peak voiding pressure (PVP) increased initially in both DM and diuretic mice. However, in DM mice, PVP dropped dramatically at and after 12 weeks. Similar changes in the capacity, compliance and emptying ability of the bladder were seen during the first 9 weeks of the diabetes or diuresis, whereas significant decline in the emptying ability of the bladder is only seen in diabetes after 12 weeks of disease in mice. Long-term insulin replacement effectively reversed most changes in bladder function. These results suggest that the transition from a compensated to a decompensated bladder dysfunction occurs 9-12 weeks after induction of DM in mice by STZ.