Abstract Background: Nocturia is night waking for voiding, is a lower urinary tract problem of anxious symptom. nocturnal polyuria, diminished capacity of the bladder either nocturnal and/or global capacity, and sleep impairment are main pathophysiologic subtypes. fluid restriction mainly awhile before the bed time, anticholinergic therapy, diuretics and hormone replacement therapy are main preventive strategies. Aim of Study: To determine the oral desmopressin efficacy and safety of in nocturia of women as a treatment. Patients and methods: - Sixty-four women with18-80 years’ age with nocturia (nocturia index score >1, more than two voids per night) were invited to attend our study. randomly assigned patients into: 32 women received different desmopressin doses (0.2, 0.4, or 0.6 mg) during dose-titration period(three-weeks), and the other 32 ones received single- blind placebo treatment for 6 or 8 weeks according to their response. Results: In single-blind phase, for desmopressin, 30 (93.75 %) patients with fifty percent or more nocturnal voids reduction against the baseline levels in comparison to only 3 (9.7%)placebo-receiving patients where (P < 0.001). The mean nocturnal voids No., sleep period till 1st nocturnal void, nocturnal diuresis, and allover day volumes changed signscantly preferring desmopressin. (P