The earlier investigation indicated that,in addition to erythritol,the erythritol mother liquor still contained other unknown sugar alcohol constituents.In this paper,the high performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC-MS) analysis were employed in order to qualitatively determine these unknown substances.To be first,the HPLC analysis was undertook using the NH2 column and Shodex SC1011 column,respectively.Based on the comparison between the mother liquor peaks and standard samples peaks,the preliminary conclusions were drawn that the unknown constituents were mainly arabitol and mannitol,as well as a few amounts of ribitol.Furthermore,the LC-MS analysis revealed that their molecular weights were coincided with that of arabitol,mannitol and ribitol.Altogether,the results provided a scientific basis for the further resource utilization of the mother liquor.