In Intercultural Communication, English euphemisms play an increasingly important role. Among all categories of euphemisms, diseases are especially hard to avoid in communication. The inappropriate expressions can easily lead to cultural conflicts. The research method of this paper is to apply the theory of Politeness Principle to specific examples of the use of euphemisms on disease. We can draw the conclusion that the absence of euphemisms will cause some problems in intercultural communication, so it is suggested that people should learn how to use them properly so as to avoid cultural conflicts.