Abstract: An algorithm for Chinese SMS text topic extraction based on lexical chain is proposed. By constructing lexical chains for each SMS text, the article’s multiple depiction clews can be reflected, and some strong lexical chains with high quality can be extracted to represent main content of this article, and as the subject phrase SMS text structure keywords sequence. Experiments demonstrate that SMS text topic from this algorithm can cover SMS text information more completely. This algorithm can remove redundancy that different keyword sequence reflect same meanings. This method outperforms the method which uses statistics to perform extraction.