To identify women with diabetes at risk of increased postvoid residual volume (PVR) and investigate the relationship of increased PVR to urinary symptoms in women with diabetes. PVR was measured by bladder ultrasonography in a cross-sectional cohort of 427 middle-aged and older women with diabetes. Participants completed questionnaires assessing urgency incontinence, stress incontinence, daytime frequency, nocturia, obstructive voiding, and diabetes-related end-organ complications: heart disease, stroke, neuropathy. Serum HbA1c and creatinine were recorded. 75% of participants had a PVR of 0-49, 13% had a PVR of 50-99, and 12% had a PVR ? 100 mL. Approximately 59% of women with a PVR < 50 mL reported at least one lower urinary tract symptom. Women with diabetes and a PVR ? 100 mL were more likely to report urgency incontinence (OR 2.18, CI 1.08-4.41) and obstructive voiding symptoms (OR 2.47, CI 1.18-5.17) than women with PVR < 50 mL. In multivariable models, poorer glycemic control was associated with an increased likelihood of PVR ? 100 mL (OR 1.30, CI 1.06-1.59 per 1.0-U increase in HbA1c). PVR volumes ? 100 mL may indicate increased risk of urgency incontinence and obstructive voiding. Glycemic control may play a role in preventing increased PVR in women with diabetes.