Nanostructured Bi2Te3 can be synthesized in 100% yield by a chemical reduction method in aqueous TeO32 solution using mild and safe ascorbic acid as reducing agent instead of toxic reducing agent commonly employed. Additionally, ascorbic acid works not only as reducing agent but also as capping agent which has an excellent oxidation resistance. In general, ascorbic acid cannot directly reduce TeO32 to metal Te due to the lower reduction potential of TeO32. Electrochemical analysis and ESI-TOFMS study showed that TeO32 changes to metal Te via easily reducible Te species with ascorbic acid [TeO2(C6H6O6)](2), and subsequently metal Te triggers the reduction of Bi species, resulting in the Bi2Te3 nanoparticles. This finding creates a path of green synthesis method for nanostructured metal tellurides which have various applications. (C) 2015 The Society of Powder Technology Japan. Published by Elsevier B. V. and The Society of Powder Technology Japan. All rights reserved.