As a study of the historical charateristics of regional language and the identity of regional people, come to the fore, the general interst in the regional studies is on the rise. Unders this context, the Jeju Dialect is considered a very precious linguistic resource since it can indicate the reality of Jeju`s culture as well as its linguistic value. It is chiefly after the second half of the 1950s that the folklore literary materials were taken from the Jeju Dialect. In this paper, the folklore literature of Jeju is divided into three periods, depending on the year of publication of the literary materials: Period I includes the materials published in the 1970s, though they have been examined since 1950s; Period II covers those materials published from 1980s through 1990s; Period III is represented by the literary materials of Jeju Dialect published in 2000s. This paper is concerned with the grammatical characterisitcs of Case Markers, Auxiliary Markers, Ending Suffixes, Connecting Suffixes, Auxiliary Conjugation Markers, Passive Expressions, Expletives in ``Gresat Work of Korean Folklore Literature 9-1,`` published in 1980. It is shown that the Adverbial Case Markers include ``-euy, deore, re, euyge, anti,`` and such words as ``masseum, and ``yang`` are used as an honorary expletive for hearers. This paper goes further to claim that such words as ``bulda`` and ``bida`` coexist to be used as an Auxiliary Conjugation Marker. As far as the Passive Expression is concerned, ``jida`` is naturally combined with verbs. In addition, it is observed that ``di``-type of dependenacy noun can appear as remnants of Middle Korean. Finally, the words such as ``ilhom, nam, gumgi`` are linguistically considered to be highly valuable.