Collection of two optically pure enantiomers in as ingle crystallization process can significantly increase the chiral separation efficiency but this is difficult to realize. Now as elf-reporting strategy is presented for visualizing the crystallization process by ad yed self-assembled inhibitor made from the copolymers with tri(ethylene glycol)-grafting polymethylsiloxane as the main chain and poly(N 6 -methacryloyl-l-lysine) as side chains.When applied with seeds together for the fractional crystallization of conglomerates,t he inhibitors can label the formation of the secondary crystals and guide the complete separation process of two enantiomers with colorless crystals as the first product and red crystals as the second. This method leads to high optical purity of d/l-Asn·H 2 O(99.9 %eefor d-crystals and 99.5 %for l-crystals) in as ingle crystallization process.I tr equires as mall amount of additives and shows excellent recyclability.