Based on the data during 1980-2002, this paper empirically analyzes the impact of economic transition and structure adjustment on income disparity and calculates its path change. The author finds that there is a long- term balanced relationship between non - state - owned rate and the income disparity. The development of non- state- owned economy is the Grarger reason for income disparity.The impact on urban resident income disparity is bigger than on rural resident income. The pull force of non- state- owned rate on resident income disparity showed stable and vibration path before 1992 and becomes obvious after 1992 and has increased since 1996. This paper also points out the related suggestions.