”Shi Jing, Si gan” interpreted a dream about bear or snake as the omen of giving birth to a boy or girl respectively, which naturally indicates a strong connection between snakes and female image in the ancient time. The author tried to identify the connection between snakes and female image in the ancient time from mythology, totemism and ancient literature in order to find out a more reasonable and appropriate explanation for the interpretation of a dream about snake as the omen of giving birth to a girl.