OBJECTIVE To assess the long-term clinical outcomes of Implantable Collamer Lens (Visian ICL; STAAR Surgical) implantation for moderate to high myopia. METHODS Retrospective observational case series. METHODS This study evaluated 41 eyes of 41 patients with myopic refractive errors of -4.00 to -15.25 diopters (D) who underwent ICL implantation and routine postoperative examinations. Before surgery, and 1 and 6 months and 1, 4 and 8 years after surgery, we assessed the safety, efficacy, predictability, stability, and adverse events of the surgery. RESULTS The safety and efficacy indices were 1.13 ± 0.27 and 0.83 ± 0.36. At 8 years, 68.3% and 85.4% of the eyes were within 0.5 and 1.0 D, respectively, of the targeted correction. Manifest refraction changes of -0.32 ± 0.73 D occurred between 1 month and 8 years. The mean endothelial cell loss from preoperative levels was 6.2% at 8 years. Two eyes (4.9%) developed clinically significant symptomatic cataract during the follow-up period. Simultaneous lens extraction and phacoemulsification with IOL implantation was successfully performed in these 2 eyes. CONCLUSIONS According to our experience, ICL implantation was overall good in measures of safety, efficacy, predictability, and stability for the correction of moderate to high myopia during the 8-year observation period, suggesting its long-term viability as a surgical option for the treatment of such eyes.