The article is on the feudal-peerage system of the Koryo˘ Age. The feudal-peerage in the Koryo˘ Age was not only related to the Royal family but to many different surname Lords. The periods of creation of the feudal lords are different between the Royal family and the family of different surnames. The first category began to be created from King Tae-jo, but the second from King Kyong-jong when Choi-Jimong was created Dong-lae County Lords. The arrangements of the feudal-peerage system, however, came up in the period of King Mun-jong. The Precedents of bestowing peerage from Tae-jo, the First King of Koryo˘, to the period just before the enthronement of Seong-jong could be classified into three groups : ① Jeong-iun(正胤), that is the succesor to he throne, ② Tea-ja(太子), the son of a king, ③ various kinds of lord that is, Kun (君), Tae-kun(大君), Kung-kun(官君), Won-kun(院君), Nang-kun(郎君). From the 13th year of King Hyon-jong, however, he changed the appellation to name the successor to the throne Tae-ja and the other sons of king Wang-ja(王子). From the 22th year of Hyon-jong, Five-ranks Peerage of Chu Dynasty of China(that is, Duke, Mrquis, Earl, Viscount, Baron) began to be applied to the Royal family of Koryo˘ and the peerage system of those came to be arranged in the period of King Mun-jong. But the system was not the same as that of China, but somewhat mixed, holding two concurrent positions ; that is, on the one hand, the degrees above Duke, Marquis, and Earl, on the other hand Three lords(三公), Secretary Office(中書令), Administrative Office(尙書令). The giving ranks of peerage to the family of different surnames began with Choi-ji-mong in the 5th year of King Kyong-jong, who was created Dong-lae County-Lord, with a feudal hamlet of 1000 houses, Then the Five-ranks Peerage System came to be arranged through King Hyun-jong to the period of King Mun-jong. There are some differences in peerage creation between the Royal Family and the different surnames. First, the titles given to the Royal Family are primarily related to the nominature of State, but the title of the lords of different surnames to the counties or districts. The second, the royal family was given the tiles of Duke, Marquis and Earl, but the lords of different surnames spread all over the Five-ranks Peerage and there was a division between County-Peerage and District-Peerage under the ranks of State Duke and County Duke. The feudal hamlet system established in the period Mun-jong had six-grades on the basis of Five-ranks Peerage, applied to both the Royal Family and the different surnames. The six grades are different from each other according to the houses of feudal hamlet : ① for Duke, Marquis and State Duke are 3000 houses, ② County-Duke 2000 houses ③ District-Lords 1000 houses ④ District Earl 700 houses ⑤ the founding members of the State 500 houses ⑥ District Baron 300 houses. The feudal hamlet system of Six Grades corresponds to the Peerage System concerning the Royal Family and the different surnames. The six grades apply not only to the Royal Family but also to different surnames. Nevertheless, a difference exists between them : the six grades of the first category chiefly apply to the ranks of Duke, Marquis and Earl, but those of the second category spread all over the Five-ranks Peerage.