Contemporary metaphor theory holds that metaphor,rather than a rhetoric method affiliated with languages,is a tool of human cognition and a process of reshaping human experience. This study,drawing upon new theories of metaphor,attempts to make an overall exploration into the conception of “disease” through collecting and analyzing a vast body of English for medical purpose(EMP) literatures. The related metaphorical expressions and conceptual metaphors from the live language were analyzed,compared and explained from a cognitive view,thereby strongly confirming the ubiquity of metaphor in EMP discourse.