本研究以語音實驗方式，分析比較日本學生及華語母語者帶鼻音韻母的聲學特質。透過時長、共振峰值及鼻音化程度，比較兩語言組/an, aŋ, ən, əŋ, in, iŋ/相異處。元音圖顯示主要不同點為日本學生沒有因銜接鼻音語境而有同華語的協同發音現象（例[a]n與[ɑ]ŋ之分）；另外，日語本身的音拍鼻音同化規則並沒有被套用於華語的韻尾鼻音發音上，但相對較長的韻尾鼻音顯示日語音拍韻律結構作用於華語音節韻律結構上。文末提供依聲學資料結果而歸納出來的教學技巧。

In this research, the acoustic features of Mandarin vowels /a, ə, i/ followed by nasal coda /n, ŋ/ pronounced by Japanese Learners of Mandarin (JLM) and Chinese Native Mandarin speakers (CNM) are compared. Acoustic measurements of interest include duration, formant trajectories and degrees of nasalization. The most pronounced differences are (1) JLM did not shift the non-high vowels along with the nasal coda, whereas, CNM demonstrated a significant anticipatory coarticulation between non-high vowels and the nasal coda (for example, [a]n vs. [ɑ]ŋ); (2) JLM did not apply the moraic nasal assimilation of Japanese to the pronunciation of Mandarin final nasal; (3) the relative duration of nasal codas pronounced by JLM is longer, indicating the rhythmic influence of Japanese (mora-timed language) on the pronunciation of Mandarin (syllable-timed language). The findings elucidate the JLM pronunciation of Mandarin vowels with nasal codas in a quantitative manner, which can be of use to Japanese learners of Mandarin and teachers alike.