本文主要以殷墟甲骨文為研究對象，在分時期分貞人組的概念下，針對甲骨文一字的構形變化問題進行研究。本文首先舉出甲骨文字的原始特徵和其對構形的影響，再對甲骨文字的構形變化，由「文字本身的變化」、「文字發展演變所致的變化」及「不同貞人組或時期間的變化」三方面分析討論。在「文字本身的變化」方面，本文指出「加增部件」、「代換部件」、「訛混部件」和「簡省部件」四種規律性現象，討論具體例子。在「文字的發展演變所致的變化」方面，以「形聲化現象」和「分化現象」探討一字的演變過程。最後「不同貞人組或時期間的變化」方面，本文指出在不同貞人組中所見的「同字異構現象」，並對「同詞異字現象」和「用詞不同現象」作進一步討論。 / This thesis is to study the structural change of a character in Yin-Xu(the old plains of Yin Dynasty) oracle bone from the viewpoint of Wu-Qi(five periods) and Zhen-Ren-Zu(the groups of fortune-tellers). First we address the primitive characteristics of oracle bone characters and their effects on the structure of characters. Secondly we discuss the structure of oracle bone characters such as [variation of components in a character], [diversity by the development of a character] and [change between different periods or different Zhen-Ren-Zu]. For the [variation of components in a character], we point out four systematic phenomena such as [increment of components], [substitution of components], [misuse of components] and [simplification of components]. On the other hand, for the [diversity by the development of a character], we discuss [phonetic symbol phenomena] and [ramification phenomena]. Finally for the [change between different periods or different Zhen-Ren-Zu], we indicate the [different structural phenomena of the same character appearing in the different Zhen-Ren-Zu], and further discuss [phenomenon of using different characters about same vocabulary] and the [phenomenon of using different vocabularies about same meaning].