Nanozyme is a type of nanomaterial that possesses intrinsic enzyme-like activity, first discovered by Chinese scientists recently. As a new type of artificial enzyme, nanozyme has the advantage of low cost, high stability, ease for mass production. More importantly, it has multi-functionality, including enzymatic activity as well as other specific nanoscale properties such as magnetics, optics, and photothermy. The emergence of nanozymes provides us with new ideas, new methods and new tools for the application of enzymic catalytic reaction in disease diagnosis. This review focuses on the application of nanozymes in disease diagnosis in recent years, including cancers, metabolic diseases, infectious diseases, neurodegenerative diseases, cardiovascular diseases and inflammatory diseases and so on. We also address the current challenges and possible directions to fulfill their prominent potential in future.