The purpose of this paper is to study the legends of local deities in Tainan to structurally deal with the conditions, paths and methods for females to become goddesses. The research results pointed out that those females who died before marriage were easier to become goddesses. It is due to the inconformity with the principle of continuing their clans in the patrilineal society, so they would fall to become unstable ghosts. However, as they were not contaminated by sex and birth giving and thus still maintained their cleanliness and chastity, they were able to transform themselves into goddesses more easily. Marriage is an important factor determining whether a female is able to become a goddess. Females in ghost marriages are harder to enter the stable status as their ancestors did, so they still have the possibilities of transforming themselves into goddesses. Females could also ascend to become goddesses by marrying a god; this is an easy and quick approach but devoid of independence. Most females who became goddesses all showed moral and miraculous achievements while they were alive; and after their deaths, they displayed their "uniqueness" or benefited the local through epiphany. They especially served the world through psychics, from "exclusivity" to "openness," and gradually expanded the foundation of their believers. This is also a key to becoming goddesses. These paths of females becoming goddesses reflected the control and depression of the patrilineal society over women and also provided us with a different point of view to rethink the theory of "gods, ghosts and ancestors" from the gender aspect.