In the long term of modern Chinese revolution and socialist construction, Mao Zedong had been confronted with many hardships and setbacks. He had put forward important ideas on setbacks that encountering setbacks is inevitable, setbacks and success often accompany each other, and it is very necessary to look on setbacks as opportunities to obtain experience. Thus there appeared Mao Zedong’s theory of setbacks being inevitable, their significance and values, and how to deal with them. Reviewing Mao Zedong’s theory of setbacks, this paper points out that it is helpful for us to confront hardships and setbacks with a correct viewpoint, and it is helpful for Chinese communists to fortify their ideals and convictions when striving for realizing the Chinese Dream of the great rejuvenation of the Chinese nation.