Objective To evaluate the effect of ultrasound‑guided iliaca fascia block (UIFB) combined with patient‑controlled intravenous analgesia (PCIA) using oxycodone on the postoperative rehabilitation in patients undergoing hip orthopedic surgery. Methods A total of 75 patients who underwent hip orthopedic surgery under spinal anesthesia were enrolled. According to the random number table method, they were divided into three groups (n=25): a PCIA group (group Ⅰ), a UIFB group (group Ⅱ), and a UIFB+PCIA group (group Ⅲ). Spinal anesthesia was routinely performed in group Ⅰ, while UIFB was performed on the affected side in group Ⅱ and group Ⅲ before spinal anesthesia. After surgery, patients in groups Ⅰ and Ⅱ were connected with PCIA pumps which contained 50 mg oxycodone and 6 mg tropisetron in 100 ml normal saline and were programmed to deliver 4  ml each time with a lockout interval of 5 min. The Visual Analog Scale (VAS) scores 6, 12, 24, 36 h and 48 h after surgery, the flexion and abduction of the affected hip joint 24 h and 48 h after surgery, and the incidences of adverse reactions, such as nausea and vomiting, itchy skin, drowsiness and respiratory suppression, etc. 48 h after surgery were recorded. The percentage of overall satisfaction and the length of hospitalization stay were recorded. The total doses of oxycodone 48 h after surgery and the effective pressing number of PCIA pump were recorded in group Ⅰ and group Ⅲ. Results In the current study, 6, 12, 24 h and 36 h after surgery, patients in group Ⅱ and group Ⅲ presented lower VAS scores than group Ⅰ (P<0.05), and group Ⅲ presented lower VAS scores than group Ⅱ (P<0.05); patients in group Ⅱ and group Ⅲ showed shorter length of hospitalization stay than group I (P<0.05), and group Ⅲ presented shorter length of hospitalization stay than group Ⅱ (P<0.05). Patients in group Ⅲ showed less oxycodone consumption, and a less effective pressing number of PCIA pump than group Ⅰ 48 h after surgery (P<0.05). Patients in group Ⅱ and group Ⅲ showed larger flexion and abduction of the affected hip joint than group I (P<0.05) and group Ⅲ showed larger flexion and abduction of the affected hip joint than group Ⅱ 24 h and 48 h after surgery (P<0.05). Patients in group Ⅱ and group Ⅲ showed lower incidences of nausea, vomiting and drowsiness than group Ⅰ (P<0.05), and group Ⅲ showed lower incidences of nausea and vomiting than group Ⅰ (P<0.05). Patients in group Ⅱ and group Ⅲ showed a higher percentage of overall satisfaction than group Ⅰ (P<0.05), and group Ⅲ showed a higher percentage of overall satisfaction than group Ⅱ (P<0.05). Conclusions Compared to traditional PCIA or UIFB alone, UIFB combined with PCIA improves the analgesic effect and the flexion and abduction of the affected hip joint, decreases the incidences of adverse reactions related to opioid analgesics, and accelerates rehabilitation after surgery.