Abstract: The evolving patterns of tone are a key to revealing the hierarchy and historical evolution of dialect tone. By analyzing the development of tone patterns, the historical evolution of Xiang dialect tone can be generalized as follows: the rising tone, in its early stages, is classified as voiceless and voiced. And now the phenomenon of semi-voiced becoming voiceless is a result of the influence of common language. Yiyang, a prefecture-level city in northern Hunan Province, has two levels of voiceless falling tone, one of which may be the overlap of southwest Mandarin. And the literary and colloquial levels of voiced falling tone in Changsha, the provincial capital of Hunan, also imply the fact that many areas in Hunan have been greatly affected by a common language that doesn’t distinguish voiced falling tone from voiceless falling tone. Its entering tone is classified into three patterns: 1. In early days, voiceless and voiced of tone are separated (in Jiangyong area). 2. The tone, in its early stages, is influence by a common language which as the same as the falling tone doesn’t differentiate voiced entering tone from voiceless entering tone. 3. The tone is blended with voiced entering tone and voiceless entering tone as a result of the universal coverage by a given common language, which is wildly known in Changyi area.

Key words: evolving patterns, Xiang dialect, the evolution of tone, dialect study