The first emperor of the Ming dynasty issued a ban on the private study of astrology in the Great Ming Code to monopolize the right of interpreting the political meanings of astronomical phenomena, otherwise some xiaoren 小人 might have abused it to disturb imperial legitimacy. In existing studies on astronomical policy in the Ming dynasty, this ban has been regarded as a serious obstacle to the progress of astronomy by interrupting the reproduction of diverse and abundant human resources for astronomy. However, researches on this subject has overlooked two important problems. (1) Although very few had an objection to the fact that the ban was mitigated in the mid-Ming period, the historical background of its relaxation has not yet been properly investigated. (2) What is more important: it has thus far gone unnoticed that some Ming scholars had made efforts to overcome the restriction of their private study of astrology and publication of books on astrology, which could have been used as primary materials for unauthorized persons’ learning of astrology in that time period and even after the relaxation of the ban. This would have had even greater implications considering the lengthy duration, for the ban was not abolished, but still remained in the Great Ming Code throughout the Ming dynasty. This paper discusses how these Ming scholars justified their own private study of astrology. I argue that they searched for a solution to that problem by transforming a traditional outlook on xiaoren.