The metaphor “cleanliness is next to godliness ” is widely accepted in real life. Recently, researchers have tried to use the methods applied in behavior and cognitive science to prove the mental reality of this metaphor. And many researchers pay a lot attention to the casual effect of physical to moral judgment. However, there have been heated debate on the direction to which physical cleansing will lead when making moral judgments, more severely or even more tolerably? Hence, it is important for us to understand how cleansing priming works for moral judgments, and what factors influence these two different directions. After referring to some related research, there are some factors people paid few attention to like the original mental states (mood) before cleansing priming, priming methods of physical cleanliness, the roles people play (actor or observer) in moral judgments, the type of moral behaviors, as well as some unknowable moderators and mediators, and all these factors could exert some distinct influences on our moral judgments. Based on these, researchers should further explore states like disgust, happiness or neutral before and after cleanliness priming. Moreover, different cleansing priming should be more precisely defined and the combination of cleansing priming with different subject roles may also make some difference. And the influence of moral scenarios together with some other mediators (such as moral self-image and political standpoint ) or moderators (like compulsive tendencies and perfect personality) on morality should also be paid close attention to, so as to reveal the mechanisms of cleansing priming in shaping moral behavior and moral cognition more correctly. What’s more, cleanliness priming in future research should be manipulated more standardly. And specific groups like criminals or judges should also be paid attention to, so as to explore the effects of cleanliness on moral judgment among these groups. Besides, owing to culture limitation of metaphor, future researches need to take culture factors into account when carrying out related researches. Given that dirtiness or cleanliness of physical environment plays such an important role in reality, future researchers should pay more attention to the role of situational factors of cleansing in morality; That is to say researchers need to attach great importance to the implication roles of cleansing clues, such as the locating place of the slogan, public service advertising or dustbin. Great importance should also be attached to the rebuilding of environment in prison, so as to make a better environment for prisoners which may help them reform better. Only in these ways, can Chinese people shape moral behaviors and cognition more correctly in this comfortable and clean environment.