龜山島方言有宜蘭方言典型的漳音特色［ũi］，也有溪北方言特有〈香姜〉類、〈香恭〉類讀［iŋ］的特點，其元音系統為／i、e、a、u、ɔ／的對稱五元音系統，與宜蘭方言的六元音不同。本文探討三個問題：（1）跟溪北的頭城、礁溪比較起來，龜山島方言是否保留更多漳音特點［ũi］以及〈香姜〉類、〈香恭〉類讀［iŋ］的特點；（2）龜山島方言元音系統的變異；（3）影響龜山島特殊方音音變的社會因素。為了回答上述問題，本文採用詞彙表，總計調查88位受訪者，年齡層有老、中、青三代，主要的分析材料來自龜山島52位居民的語料。我們的調查發現，與頭城、礁溪相較起來，龜山島方言保存更多漳州音特色［ũi］及〈香姜〉類、〈香恭〉類讀［iŋ］的特點。龜山島方言是／o／、／ɔ／不分的對稱五元音系統，由於結構對稱，並且是最自然、無標的元音系統，因此極為穩固，少有變異。年齡是影響龜山島方言音變最顯著的社會因素，性別的影響並不顯著。

The dialect of Guishan Island in Yilan County has the typical final[ũi]of the Changchou-type accent as well as the final[iŋ]found in other dialects. The vowel system /i, e, a, u, ɔ/ of this dialect is also different from that of other dialects in Yilan (/i, e, a, u, ɔ/). This paper examines the dialect of Guishan Island to determine if it preserves the feature[ũi] of Changchou-type accent more than other dialects in Yilan County; the paper also looks at sound variation and change in the Guishan Island dialect and the social factors that result in the change. With vocabulary tables, I investigated 88 informants from different generations. The main materials for analysis are from 52 senor, middle-aged and young informants, all inhabitants of Guishan Island. The study shows that the dialect of Guishan Island does preserve more of [ũi] and[iŋ]than the dialects of Toucheng Town and Jiaoxi Town. The vowel system of this dialect does not distinguish /o/ from /ɔ/, and its vowel system /i, e, a, u, ɔ/ makes this dialect stable with little variation. Lastly, the main social linguistic factor that brings about sound change appears to be age rather than gender.