Objective To explore the median effective concentration (EC50) and 95% confidence interval (CI) of ropivacaine for fascia iliaca compartment block (FICB) before positioning for intrathecal anesthesia in elderly patients with hip fracture. Methods A total of 30 patients, aged 70‒90 years old, American Society of Anesthesiologists Ⅱ or Ⅲ, who were scheduled for hip fracture surgery from September 2020 to March 2021 were selected. FICB was performed under the guidance of ultrasound before positioning for intrathecal anesthesia. The pre‑set total volume of ropivacaine was 30 ml, with an initial concentration of 0.3%. The Dixon sequential method was used to determine the concentration of ropivacaine. The EC50 of ropivacaine and its 95%CI were calculated according to Probit analysis. The Visual Analogue Scale (VAS) scores were recorded before FICB, 15 min after FICB, and at positioning. The incidences of complications (bleeding, hematoma and local anesthetic intoxication) were recorded. Results The VAS scores 15 min after FICB and at positioning decreased, compared with those before FICB (P<0.05). There were no complications including bleeding, hematoma and local anesthetic intoxication. The EC50 of ropivacaine and its 95%CI for ultrasound‑guided FICB before positioning for intrathecal anesthesia in elderly patients with hip fracture was 0.14% (0.11%‒0.16%). Conclusions The EC50 of ropivacaine and its 95%CI is 0.14% (0.11%‒0.16%) for ultrasound‑guided FICB before positioning for intrathecal anesthesia in elderly patients with hip fracture.