Yin and Yang is a meta-category concept of Classical Chinese Philosophy. And Twelve Chinese Zodiac Signs is vital component of Traditional Chinese Culture. The generalization in The Books of Changes that the alteration of Yin and Yang makes Tao is widely revealed in all aspects of Traditional Chinese Culture. And the ideology of Yin and Yang is frequently felt in the sequence of the Twelve Chinese Zodiac Signs, resulting in more difficulty in understanding the two concepts. Some ancient recognition made their analyses from the physical and habitual traits of the Twelve Chinese Zodiac Signs (of individuals), while others from the Hexagram Symbols. Varied and full of fun as they may seem, the ideology of Yin and Yang is mentally rooted in the Chinese people, revealing the Symbol-Metaphor Thinking of the Chinese nation.