According to traditional Chinese astrology, the rabbit is master of years which fall under the fourth celestial stem combined with the fourth terrestrial branch.
古代中國人相信，兔，即「吐」的諧音。他們認為兔子只有雌性，沒有雄性；雌兔望月而孕，由口中「吐」子。因此，由月亮明暗的程度，還可以判斷兔子生產的多寡。