Abstract: The name and meaning of "Dunhuang Changed-letters" have been ambiguous in the past study and readings. People used to misuse the concept by broadening or narrowing its denotation and by indicating two meanings with one single name. This pape puts forward a suggestion to clarify the useage, subject to historical and realistic factors, with "Dunhuang Changed-letters" indicating the concept in broad sense and "Pure Dunhuang-letters" in narrow sense.