Genitourinary syndrome of menopause (GSM) is a common complication secondary to estrogen depletion which leads to tissue changes in the female genitourinary tract. Here, we sought to investigate the short- and long-term effects of CO laser therapy on symptoms of GSM in postmenopausal women. In this clinical trial, 47 postmenopausal women with symptoms of GSM were included. Participants underwent vaginal and extra-vaginal CO fractional laser treatment in three sessions, with intervals of one month between each session. Symptom severity, including itching, dyspareunia, vaginal discharge, and dryness, was assessed at each session using a modified Vaginal Health Index (VHI), where the intensity was rated on a Visual Analog Scale (VAS) from 1 to 10 (1 indicating minimal symptoms and 10 representing maximum severity). Additionally, the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) was administered. Patients were followed for one to three years after the final laser treatment session. The scores of all subscales, including itching, dyspareunia, urinary incontinence, vaginal discharge, and dryness, improved significantly following three sessions of CO fractional laser ( values<0.001). However, except for the urinary incontinence domain (=0.058), none of the symptoms maintained improved after one to three years from the last intervention. CO fractional laser treatment is appropriate for treating symptoms related to GSM. But it seems that it needs to be used continuously for the maintenance effect on itching, dyspareunia, urinary incontinence, vaginal discharge, and dryness. The exact timing of laser sessions should be identified in further studies since the beneficial outcomes of the intervention seem temporary.