Abstract: To explore the properties of daily flow variation in the Yangtze River and its prediction by using a new approach, the issue of chaotic property of daily flow at Yichang station has been addressed systematically and fully.The findings from this comprehensive exploration are divided into several parts.This paper contains the second part,in which the stress is put on optimum determination of embedding dimension.The determination of embedding dimension is also very important for chaotic analysis.Three methods are applied to this determination.They are saturated correlation dimension,false nearest neighbors and real vector field.Their properties,advantages and disadvantages are analysed in this paper.The results show that the optimum embedding dimension must be determined based on comprehensive analysis and in combination with consideration of optimum wide window.