Generally, the doctrines of Cult are very bizzare and difficult to be accepted by ordinary people with common sense. But there have been many people who are engaged in cult and had many problems. So understanding the psychological process of engaging in cult is essential to understand cult. Several factors which influence people to cult are known. Confronting problems which can not be solved with previous perspectire and ability, have cognitive discordance and emotional distress. At that time, people open their mind to MRM. And the positive, warm and intense human relationship in cult press the people to be engaged in cult. And some unfamiliar and supernatural experiences in cult make them be engaged in cult. Brain washing seems to be different from conversion in cult, because there is no compulsive physical and psychological restraint in cult which is essential in traditional brain washing. So people seemed to be engaged in cult, consciously or unconsciously, voluntarily. Traditionally, conversion religion has been regarded as very passive things. But, in these days, the active role of charismatic group is important to understand cult, In order to study, cult, charismatic group should be studied to. As cult has not only a religious aspect but also social, psychological, familial and cultural aspects, a comprehensive view to cult can be one way to study human inner world.