Wang Renbo, who was one of Lisu in Yunnan Province, created ethical character only by himself in 1920s. The character was named Zhushu, for it was written on the bamboo at the very beginning.This dissertation focuses on Literacy Text-book written by Wang Renbo for the first time and shows the complete and systemic study on Zhushu which was a very special example in the written language history, based on the author' s field research. The dissertation may offer definite reference to the General Written Languages, Written Linguistic Comparison, Written Language History and other nation's writing systems.The dissertation is divided into:Chapter Ⅰ: Introduction. This part introduces the general situation of formation, the materials, research history and actuality about Zhushu. It elucidates the research thought and methods as well as the special significance.Chapter Ⅱ: The Origin of Zhushu. The detailed research and analysis on 243 Zhushu characters has been made, following the classification standard in the book of The Dictionary of Naxi Pictograph written by Fang Guoyu. It explains the word-formations and methods used in the analysis.Chapter Ⅲ: Corresponding Relations between Zhushu Characters and Lisu Language Units. The characteristics of Lisu language are analyzed in this chapter. Zhushu is one kind of proper syllable systems because it can note all Lisu language syllables.Chapter Ⅳ: Study on the Self-made Zhushu Characters. Pictograph, self-explanatory and associative compounds are three kinds of word-formation in the self-made Zhushu characters. The main conclusions are : 1、 The pictographs are quite nonobjective and the strokes of them tend to be straight lines even from the very beginning of character formation. 2、 There are 114 self-explanatory characters and it is almost 45.5% in Zhushu. There are various kinds of self-explanatory characters and they may be divided into two sorts: pure self-explanatory and self-explanatory with denotation. Pure self-explanatory includes single and combined ones. Also, self-explanatory with denotation may be divided into two sorts according to the character origin: one is pictograph + self-explanatory with denotation, the other is associative compound + self-explanatory with denotation. 3 、 Associative compounds are consisted of pictograph + pictograph, pictograph + an indefinite sign and pictograph + self-explanatory. 4、 The process of Zhushu word-formation was not from pictograph to pictographic signs and abstract signs but nearly an abstract leap. Most characters stand for both meanings and syllables originally so that Zhushu is a primordial syllable character with some pictograph function.Chapter Ⅴ: Study on the Derived Characters. There are two kinds of derived characters: derived compound characters and derived characters. Pure derived compound character and derived character with sign are the same farther subdivisionsas pure derived and changed derived ones in the derived characters. The dissertation elucidates that Zhushu is the imitation of Geba that notes every syllable with one character only, following the shape of Chinese characters. Zhushu is one kind of self-made minority characters with some derived Chinese and Geba characters.Chapter VI: Study on the Variant. Homophones are the variants in Zhushu. The essential difference of variants between Chinese and Zhushu is that variants in Zhushu are the original creation with times, area and multi-culture characteristics on the background of Naxi and Chinese culture. It is quite different from Chinese variant which is the result of different times, areas and writing materials. The essential cause of Zhushu variant is the feedback of multiform objects. The variants in Zhushu can be the mirror of Lisu culture. Zhushu is one kind of immature syllable characters due to its variants.The characters of Zhushu are summed up in the conclusion chapter.There is an appendix of Zhushu characters to Lisu language corresponding syllables at the end of the dissertation.