Objective: The aim of this study was to reveal the frequency and impact of perforating venous insufficiency (PVI) in chronic venous insufficiency (CVI) of lower extremity (LE). Materials and Methods: Between 2012 and 2017, a total of 1154 patients [781 females (67.68%) and 373 males (32.32%), 228 (19.76%) unilateral and 926 (80.24%) bilateral LE] were examined using Doppler ultrasound (US). A total of 2080 venous systems of LEs [31.4% male (n=653) and 68.6% female (n=1427); 1056 left LEs (50.77%) and 1024 right LEs (49.23%)] were examined. All patients had symptoms of venous insufficiency (VI). Results: PVI was revealed in 27.5% (n=571) of LEs. Varicose veins (VVs) related with perforating vein (PV) were revealed in 44.7% of LEs (n=929). PVI was observed in 50.91% of patients with chronic deep venous thrombosis (DVT), 64.41% with deep venous insufficiency (DVI), 59.81% with great saphenous vein (GSV) insufficiency, 68.49% with small saphenous vein (SSV) insufficiency, 58.65% with accessory GSV insufficiency, and 58.77% with PV associated with VVs. There was a statistically significant relationship between PVI and chronic DVT, DVI, GSV, SSV, and accessory GSV insufficiency (p<0.001). A significant relationship was observed between the increase in PV diameter and the presence of PVI (p<0.001). Conclusion: PVI is quite common in combined VI, and PV evaluation should be a part of LE venous system examination.