Purpose: To develop a strategy for the iliac vein stenting in patients with a combination of the left common iliac vein (LCIV) compression stenosis and pelvic venous insufficiency (PVI). Methods: This prospective comparative cohort study included 55 patients with hemodynamically significant LCIV stenosis out of 285 females with PVI screened in 2014–2022. All 55 patients underwent duplex ultrasound, multi-detector computed venography, ovarian venography, and multiplanar pelvic venography. Patients underwent LCIV stenting or the left gonadal vein (LGV) embolization as the primary intervention. The endpoints (chronic pelvic pain [CPP] relief, patency of stents, and reduction in pelvic venous reflux [PVR]) were evaluated 1 and 10 days, as well as 1, 6, and 12 months after the procedure. All patients received antithrombotic therapy after the interventions. Results: The primary LCIV stenting was performed in 49 patients and resulted in the CPP relief in 69.4%, pain reduction from 7.9±1.3 to 1.7±1.1 visual analog scale (VAS) scores (p=0.005), and substantial reduction of PVR in LGV (from 4.3±0.6 seconds to 1.9±0.3 seconds, p=0.003). The LGV embolization as the second stage of treatment was performed in 30.6% of patients with the LGV reflux greater than 5 seconds as a possible cause for the CPP persistence. The primary LGV embolization failed in 100% of patients (no changes in CPP and PVR). The LCIV stenting at the second stage resulted in the CPP relief within 10 days and the pelvic venous reflux (PVR) reduction. There were no complications of stenting, and the patency of stents in the follow-up period was 100%. Postembolization syndrome occurred in 9.5% of patients. No thromboses of the veins of the pelvis and lower extremities were identified. Conclusion: Treatment of patients with a combination of LCIV compression and PVI involves staged endovascular interventions: the LCIV stenting should be considered the first-line treatment, while the LGV embolization is performed when the PVI symptoms persist for more than 6 months and is not acceptable as the first-line treatment. Clinical Impact The developed strategy of endovascular treatment for the combination of left common iliac vein (LCIV) and pelvic venous insufficiency (PVI) provides an effective elimination of chronic pelvic pain (CPP) and reflux in the pelvic veins and avoids unnecessary embolizations of the gonadal veins, thereby eliminating possible risks related to complications of embolization. The use of antithrombotic therapy is an effective and safe approach for preventing venous thromboembolic events after endovascular interventions.