Abstract: OBJECTIVE To optimize synthetic process of sugammadex sodium. METHODS Sugammadex sodium was synthesized from γ-cyclodextrin through selective bromination using the key immediate 2 and subsequent thioetherifation. RESULTS The goal product was structurally identified by ¹H-NMR and HRMS, and the total yield was >30.0%. CONCLUSION This process has the advantages of low-cost, simple operation and good prospects for commercial scale-up.