本文主要從句法(Syntax)與音韻(Phonology)的介面關係來探討東勢客語的陽平、陰平及陰去變調現象。本研究以語料庫為根據，觀察東勢客語變調的主要型態，並從句法與音韻的介面來定義變調範域(Tone Sandhi Domain)，包括音步(Foot)、音韻詞組(Phonological Phrase)、語調詞組(Intonational Phrase)等等。本文也發現變調規則必須以循環模式(Cyclic Mode)運作，而且三個變調規則的屬性皆不相同。陽平變調受音步規範、陰平變調較受音韻詞組規範，而陰去變調則不受音韻結構限制。 / This thesis explores the Yangping, Yinping and Yinqu Tone Sandhi Rules (YATSR, YITSR, YQTSR) in Dongshi Hakka from the perspective of the interface between syntax and phonology. According to a Dongshi Hakka Tone Sandhi (DHTS) corpus, this thesis presents the predominant tonal patterns of these rules, and defines the tone sandhi (TS) domain at the interface between syntax and phonology, including foot, phonological phrase, intonational phrase and so on. This thesis concludes that tone sandhi rules must apply in a cyclic mode, and that the three rules are subject to different prosodic structures. YATSR is conditioned by the foot, YITSR is better defined by the phonological phrase, while YQTSR is not structurally-bound.