This study is on the Astronomical Thought of Chun-Qiu-Zuo-Chuan, a history book of old China. Astronomical phenomena were very important in ancient China. For it is not only making calender or knowing seasons but also interpreting every important things of their nation. Old Chinese people had been thought astronomical phenomena as a kind of warning or indication for the future and the past of their emperor. They had been thought the heaven and mankind are co-related and working together, so they slit all of their area in accordance with constellations of the sky. Therefore they had been observed every astronomical phenomena, constantly and carefully. For the result of their diligent efforts to astronomical phenomena and constellations made old chinese calenders almost perfectly and precisely. Those calenders were used for farming, governing, and other propose. Astronomical phenomena had been used in so many arts of daily life, so they worshiped them, gave special meaning to them. Using exact calender and the thought of the heaven, the earth, and mankind are all co-related each other, and the connection of astronomical phenomena and Yin-yang Wu-xing, and Liu-Qi are representative features of the astronomical thought of Chun-Qiu-Zuo-Chuan. Those can be an effective method to understand the period of Chun-Qiu in old China. Because those had inherited the astronomical thought of the period of Xi-Zhou and Chun-Qiu-Zuo-Chuan is the basic document to study the period of Chun-Qiu. Therefore the astronomical thought of Chun-Qiu-Zuo-Chuan can be the astron- omical thought of Chun-Qiu period of China, and that is the reason why more research must be fulfilled to astronomical thought of Chun-Qiu-Zuo-Chuan, in future.