Background: Local anesthesia (LA) is widely used in knee arthroscopic surgery but not in ankle arthroscopy. Objective: To understand the effectiveness and safety of LA combined with ropivacaine in pain control for ankle arthroscopy. Study Design: Retrospective cohort. Methods: We retrospectively collected data for patients who underwent ankle arthroscopy from April 2012 to April 2017. Patients were grouped by anesthesia method: LA, LA with ropivacaine (LA+R), spinal anesthesia (SA), and SA with ropivacaine (SA+R). Intra- and postoperative visual analog scale (VAS) scores, complications, doses of supplemental pain medication, hospitalization cost and duration, and satisfaction with pain control during hospitalization were analyzed. Results: The study included 276 patients (LA: 93; LA+R: 124; SA: 31; SA+R: 28). The LA and LA+R groups had significantly higher intraoperative VAS scores (LA vs. SA, p = 0.001; LA vs. SA+R, p = 0.002; LA+R vs. SA, p = 0.00; LA+R vs. SA+R, p = 0.00), but fewer complications, than the SA and SA+R groups. The LA+R and SA+R groups had significantly better outcomes for postoperative pain control (LA vs. LA+R, p = 0.01; LA vs. SA+R, p = 0.01; SA vs. SA+R, p = 0.01; SA vs. LA+R, p = 0.03) and required less supplemental pain medication. Hospitalization cost was lower and duration shorter in the LA and LA+R groups than in the SA and SA+R groups. There was no significant difference in satisfaction among the four groups. Limitations: This was a single-center retrospective and relatively short-term study. Conclusions: LA+R which could be safely applied in ankle arthroscopy provided satisfactory pain control, reduced postoperative pain intensity, fewer complications, shorter hospital stay, and good cost-effectiveness. It can be safely applied in ankle arthroscopy for the specific patients with ankle osteoarthritis.