According to the connotation and function mechanism of urban -rural interaction development, this article measured the provincial urban - rural interaction development levels of the year 1995 - 2004 in China by establishing comprehensive evaluation indicators system, and decomposed the regional difference of urban - rural interaction development levels in China by Theil index and analyzed its changing tendency. The results indicate that the whole urban - rural interaction development level is not high in the latest ten years ; the regional difference of urban - rural interaction development level and its changing tendency are very obvious. We should also pay attention to the difference of urban - rural interaction development level in the inner of every area, especially in the eastern area.