I take the religious thought of Shugendo as a common thinking pattern of religious leaders-Shugenjas-who practice magicoreligious acts using the supernatural power initiated by mountain austerities. The purpose of this report is to make clear their thinking pattern. In order to achieve this object, I will analyze the process of their religious thinking. Practising austerities in a sacred mountain, Shugenjas are demanded to awake their Buddha-Nature, which they possess by nature and yet they do not realize, by the doctrine of his sect. On the other hand, they must pray for taking away their believer's bad fate which causes their misfortune. At the same time they must explain to their believers, by the help of the Shugendo doctrine, why they can give good fortunes to them. Thus has been formed the religious thought of Shugenjas. Usually they say, "Practising austerities in a mountain, I have attained the same stage as the Buddha who can take away believer's misfortune. Therefore I am able to give good fortunes to my believers, using the supernatural power of the Budda." Moreover, when they believe that they can help their believers by religious actions, their religious thought is turned into a strong belief in their mind as it is proved to be real.