Dreams are a normal phenomenon of human physiological and psychological activities. Dreams are formed by various internal and external environmental stimuli during sleep plus some memory traces in normal life. Dreams are an extension of daytime thoughts and behaviors, i.e., “when you think about something, you dream about it at night”. Dreams have the function of releasing stress and maintaining psychological balance. Some dreams are the fulfillment of wishes, and we can get pleasure in dreams that we cannot get in reality. Therefore, having dreams does not necessarily mean neurasthenia.