Objective To explore the therapeutic effect of transumbilical single-port laparoscopic high uterosacral ligament suspension(HUS)and iliacpubic ligament fixation(ILF)in the treatment of pelvic organ prolapse(POP)mainly caused by middle pelvic defects.Methods Clinical data of 15 cases of POP with middle pelvic defects from June 2017 to June 2023 were analyzed retrospectively.The HUS and ILF were performed by transumbilical single-port laparoscopy.At one year after operation,gynecological examination(POP-Q system)and maximum straining pelvic MRI examination were performed for objective evaluation.The Pelvic Floor Distress Inventory Short Form(PFDI-20)and Pelvic Organ Prolapse-Urinary Incontinence Sexual Questionnaire(PISQ-12)were used for subjectiveevaluation.Results Theoperationtimewas 65-135 min(mean,102.9±16.3 min),thebleedingvolumewas 20-50 ml,and the postoperative hospital stay was 6-9 d.Follow-up time ranged from 6 to 72 months(mean,42.8±22.3 months),among which 14 cases were≥12 months.No pelvic pain,lumbosacral pain,urinary retention and thread exposure occurred.Stress urinary incontinence(SUI)occurred in 1 case at 1 year after operation.Surgical failure was noted in 1 case(degree Ⅱ),the objective success rate being 93.3%(14/15).At 1 year after operation,the distance from the anatomical landmarks of pelvic MRI to the pubococcygeal line(PCL)was significantly higher than that before operation(P<0.01),and the PFDI-20 and PISQ-12 scores were significantly better than those before operation(P<0.01).Conclusions Transumbilical single-port laparoscopic HUS and ILF is a safe and effective mutual aid procedure for the treatment of POP mainly caused by middle pelvic defects with surgical indications,which can improve pelvic floor function and quality of life.It is simple and easy to perform with low cost of consumables,which is suitable for primary hospitals.