The study is an attempt to investigate on the features of using Idioms in "HongLouMeng", a Chinese literature. While classifying and analyzing idioms used in "HongLouMeng". The study conclude that there are two categories of the features of using Idioms in "HongLouMeng". One is the features in style such as number of letters and signal article. The other is the features in terms of content such as metaphor, replaceability and similarity. First, number of letters. Based on the number of letters, the idioms are classified into four-lettered idioms and non four-lettered idioms which consist of more or less than six letters. Chengyu(成語) is commonly four-lettered, while Suyu(俗 語) is mostly six lettered. Xiehouyu(歇后語) has the largest number of letters since it has to be considered with preceding and following letters. Second, signal articles. The articles such as ‘俗語說(Suyushuo)’ helps idioms to be clear with the intended meaning. Third, metaphor. As the almost every idiom is used as a figurative expression, idioms in "HongLoumeng" also tend to be has same effect. Forth, replaceability. Suyu(俗語) can be replaced by Chengyu(成 語) or Xiehouyu(歇后語) and vice versa. The virtue of the author's fluent commend of language allows the replaceability between idioms, in the way of using Chengyu(成語) or Xiehouyu(歇后語) to implicate Suyu(俗語). Fifth, similarity. Throughout "HongLouMeng" a number of idioms were replaced into similar expressions with same meaning which use a new word or rephrase the order of words. Idioms which contain same lessons and messages are also found numerous times with completely different structure and words. Replacing idioms instead of repeating exactly same expression shows the outstanding linguistic ability of author. The study on the five features would help to understand idioms in "HongLouMeng" more clear and make it much interesting. The author's fluent commend of language is worth to be consideredfrom various angles as it plays important role in a linguistic and a culturological points of view.