Transvaginal mesh (TVM) can increase the durability of vaginal surgical procedures for pelvic organ prolapse (POP) and may be indicated in certain situations despite concerns about mesh-related complications. In addition, the expense of commercial mesh kits has limited their use. The effectiveness, safety, and cost of a self-cut mesh procedure compared with a commercial mesh-kit procedure for the surgical treatment of women with POP is unclear. To assess the 1-year effectiveness and safety of self-cut titanium-coated polypropylene mesh compared with a precut commercial mesh kit for the transvaginal surgical treatment of women with severe symptomatic POP. This multicenter randomized noninferiority clinical trial was conducted at 11 hospitals in 8 provinces of China. A total of 336 women with symptomatic stage 3 to 4 POP were enrolled between January 22, 2018, and November 11, 2019, with follow-up through December 11, 2020. Participants were randomized to receive a TVM procedure using either self-cut mesh (self-cut mesh group) or a precut commercial mesh kit (mesh-kit group), both of which used the same titanium-coated polypropylene mesh. The primary outcome measure was composite surgical success at 1 year, which was defined as the absence of vaginal bulge symptoms, no additional retreatment for POP, and no vaginal prolapse at or beyond the hymen. Secondary outcomes included symptom-specific pelvic floor function and quality-of-life measures as well as perioperative complications, including mesh-related complications and hospitalization costs. Complications were categorized using the Clavien-Dindo system (with grade 1 indicating any deviation from the normal postoperative course but not requiring grade 2-4 interventions; grade 2, need for pharmacological treatment, blood transfusion, and/or total parenteral nutrition; grade 3, the need for surgical, endoscopic, and/or interventional radiological procedures; and grade 4, life threatening). Among 336 female participants (mean [SD] age, 63.3 [5.9] years; all of Chinese ethnicity), 169 patients were randomized to the self-cut mesh group, and 167 were randomized to the mesh-kit group. Three patients were unavailable for follow-up after 1 year. In the intention-to-treat analysis, 162 women (95.9%) in the self-cut mesh group had outcomes that met the definition of surgical success; this result was noninferior to the surgical success rate observed in the mesh-kit group (146 women [87.4%]; risk difference, 8.5%; 95% CI, 2.2%-14.3%; P = .006). The frequency of Clavien-Dindo grade 1 to 3 perioperative complications was not significant between groups (12 of 166 women [7.2%] in the self-cut mesh group vs 20 of 161 women [12.4%] in the mesh-kit group; P = .14). Vaginal mesh exposure rates in women examined at 1 year were similar (4 women [2.4%] in the self-cut mesh group vs 8 women [4.8%] in the mesh-kit group; P = .23). Median (IQR) total hospitalization costs were $3663.00 ($3258.90-$4495.10) in the self-cut mesh group vs $6144.00 ($5434.90-$7160.20) in the mesh-kit group (P < .01), representing savings of $2481.00 (40.4%) with the use of self-cut mesh. In this clinical trial, the composite surgical success rate of a self-cut mesh procedure was noninferior to that of a commercial mesh-kit procedure using the same titanium-coated polypropylene mesh and reduced hospitalization expenses by 40.4%. These findings suggest that the use of self-cut mesh procedures may be advantageous for the surgical treatment of some women with severe POP, particularly those in countries with low and middle income. ClinicalTrials.gov identifier: NCT03283124.