This study was to analyze the philologicalcharacterofHuangdizhaijing(黃帝宅經). Huangdizhaijing isafirststagescripturesofYangzhaiFengshui(陽宅風水)whichisthe firstlymentionedbookinSikuquanshu(四庫全書).Huangdizhaijingisanobligatory book to read to understand the palace ofancientdynasty as wellas generalhousing of people. Huangdizhaijing measured housing conditions divided into Yangzhai(陽宅) and Yinzhai(陰宅).The contents succeeded traditionalYangzhaiguan(陽宅觀)which values direction(方向)andJiri(吉日).Thatis,classifying Yangzhaiinto24directionsbasedon QiofYinYang(陰陽之氣)theory,generalcontentsofHuangdizhaijingexplainsregulatory rulesand propitiousday in accordancewith theYangzhaimathematicalprinciplesand archaeology through Jixiongshenshalun(吉凶神煞論).Huangdizhaijing includesthekernel ofunderstanding thechinesearchitectsystem andhousing culturebecauseitdescribes closereciprocalinfluencesbetweenmanandhouse. It seems that the author of Huangdizhaijing is not the emperor but he was represented by descendants who systemized the idea ofHuangdizhaijing in Yangzhai shu(陽宅書).Being theremany ofdocumentspresentedby emperorlikeHuangdineijing (黃帝內徑),Itiscountedthatthereasonoftherepresentingemperoristoshow offits originhaslongandauthoritativehistory. Itseemsthatthepreserved period ofwriting Huangdizhaijing isTang(唐)dynasty, butcounting thatvariousYangzhaishuprevailed,Huangdizhaijing'scontentshasmuch in common with Dunhuangben(敦煌本), and it valued Menfazhidu(門閥制度) of Weijinnanbeichao(魏晉南北朝) dynasty,the many ofthe contents of Huangdizhaijing shouldbe formedbeforeTangdynasty. The exiting editions ofHuangdizhaijing could be divided into generally 8 kinds:① Zhengtongdaocangben(正統道藏本) ②Yimenguangduben(夷門廣牘本) ③Jindaimishuben(津 逮秘書本) ④Shuofuben(說郛本) ⑤Gujintushujichengben(古今圖書集成本) ⑥ Sikuquanshuben(四庫全書本)⑦Xuejintaoyuanben(學津討原本)⑧Dunhuangben(敦煌本)

This research was to analyze the direction ideas of residential Feng Shui. In ancient China residential places were been established by Xiangzhai(相宅) and Buzhai(卜宅) usages. And ancient Chinese always considered geographical features of mountains and waters for setting up their living places. Geographical features were also considered importantly in representative residential Feng Shui books, Zhaijing(宅經) and Yangzhaisanyao(陽宅三要). In Zhaijing, 24 direction ideas are co-related with Fagui(八卦) and GanZhi(干支) theories, and they are most important residential Feng Shui direction theories. The basic thoughts of 24 direction ideas of Zhaijing were already formed in Qin(秦) dynasty and modified in early Han(漢) dynasty. In Zhaijing, residential places were splited into Yangzhai(陽宅) and Yinzhai(陰宅) according to YinYang's Qi directions. Those theories were actually formed from meticulous observations on changing processes of YinYangWuXing(陰陽五行)'s Qi(氣). Constantly changed Qi of YinYangWuXing were studied by old chinese people from the observations on the sun, the moon, the five stars, the Great Bear, and ErShiBaXiu(二十八宿). The origin of Zhaijing's direction ideas is the direction system of ShiPan(式盤) in Qin and Han dynasty. On ShiPan TianGan(天干)․Dizi(地支)․Fagui․TianDiRenGui(天地人鬼) were arranged very systematically into four and 24 directions. DongxiSizhai(東西四宅) theories of Yangzhaisanyao had edited more lately than Zhaijing(宅經), and formed according to Fagui(八卦)‘s YinYang(陰陽) principles. But the basic ideas is same with Zhaijing's. It proves that residential Feng Shui theories were constantly improved and modified. And both residential Feng Shui direction ideas of Zhaijing and Yangzhaisanyao are the general ideas in old china. The point of that ideas is Sky's four or 24 directions are correspondence with the earth's. It came from the traditional thoughts that Heaven, Earth, and mankind are co-related and influenced each other according to Qi's changing processes. Gather up above mentioned, the direction ideas of residential Feng Shui is a systematic thoughts of old chinese for harmonizing Tian-Di-Ren-Gui, and is their specific methods for harmonizing the nature's Qi, mankind and spirits.