長汀客家話是指分布於福建省西南部長汀縣的縣城及城郊的方言。長汀客家話的連續變調現象不管在語料描述上或理論分析上都殘留了一些問題。在語料描述方面，長汀話連續變調描述上，仍有紛亂的情形；而在理論分析方面，長汀客家話的連續變調現象，尤其是三子組變調方向性上的預測，無異是對於現有音韻理論的一大挑戰。學者們曾嘗試試著由不同的音韻學理論來預測三字組的變調方向，不過，到目前為止似乎並沒有一個十分完善的分析。本研究重新調查並分析長汀客家話二字組和三字組的連續變調現象。在語料描述方面，我們觀察到了文獻上未記載的連續變調現象。在理論分析的部份，我們採取優選理論來處理長汀客家話的變調。在二字組方面，我們找出了變調的動機；在三字組方面我們成奶F預測了三字組的變調方向性。 A review of the existing literature on Changting tone sandhi reveals some important points worthy of attention. Descriptively, though field-work has been conducted on Changting tone sandhi, no consensus has yet been reached concerning which tonal combinations are subject to undergo tonal changes. Theoretically, though some researchers have attempted to provide analyses to account for the notorious directionality issue in tri-tonal sandhi, no promising analyses have yet been produced. In this study, the author conducted fieldwork to collect mono-tonal, bi-tonal and tri-tonal data of Changting to clarify the tone sandhi phenomenon and to propose analysis of the collected tone sandhi data. After collecting and comparing our collected data with those in the existing literature, the author found this study's observation of tone sandhi is richer than those reported in the existing literature. Two additional tonal changes which had not yet been reported are observed in this study's data. In analyzing bi-tonal sandhi, the author discovered that tonal changes in Changting are triggered by the tendency for tonemes to agree in intersyllabic position. They are accounted for by five OT constraints. As for tri-tonal sandhi, we propose three additional constraints that successfully predict the directionality in Changting tri-tonal sandhi.