Abstract: Relying on a corpus of thirty narrative texts and taking prosodic words as the basic unit of analysis,the present study explores the roles of pitch and duration in sentence accent in discourse context.The results show that the relative pitch range of prosodic words contributes dominantly to sentence accent.Furthermore,the roles of pitch and duration in sentence accent are affected interactively by sentence pitch range and the rank of prosodic words.In normal prosodic words,first-level sentence accents are realized by the mutual performance of pitch and duration while second-level sentence accents mainly depend on the variation of pitch.In strengthened prosodic words,the role of duration in sentence accent is more significant when sentence pitch range is more compressed.Finally,it has been found that the correlation between pitch and duration is influenced primarily by the strength of prosodic words.In weakened, normal and strengthened prosodic words,the correlations between pitch and duration are positive,null,and negative respectively.