Abstract: Objective To compare the effect of ultrasound-guided pericapsular nerve group (PENG) block combined with suprainguinal fascia iliaca (SIFI) block and traditional fascia iliaca compartment (FIC) block on postoperative pain in elderly patients undergoing total hip arthroplasty (THA). Methods A total of 50 elderly patients who were scheduled for total hip arthroplasty were enrolled. They were randomly divided into two groups (n=25). Group PS underwent ultrasound-guided PENG block combined with SIFI block, while group F received ultrasound-guided FIC block. The Visual Analogue Scale (VAS) scores at rest and during movement before nerve block (T₀), 30 min after nerve block (T₁), 6 h (T₂), 24 h (T₃) and 48 h (T₄) after surgery, sensory block in the mid-thigh at T₁, quadriceps motor block rate at T₂, cumulative fentanyl consumption within 24 h and 24-48 h after surgery, postoperative analgesia satisfaction scores and related complications were recorded. Results Group PS presented lower VAS scores at resting and during movement at T₁ to T₄ than group PS (P<0.05). The cumulative fentanyl consumption within 24 h and 24 to 48 h after surgery in group PS were lower than those in group F (P<0.001). Group PS also showed higher postoperative analgesia satisfaction than group F (P<0.05). The lateral and medial sensory block rate of the middle thigh were higher in group PS than those in group F (P<0.01). The quadriceps motor block rate were lower in group PS than that in group F (P<0.001). Conclusions PENG block combined with SIFI block is superior to traditional FIC block, which can provide good postoperative analgesia, reduce postoperative opioid consumption, and reduce the incidence of quadriceps motor block, which is a clinically optional analgesic method after hip surgery.