The kit is used for quantitative determination of C-reactive protein in human serum, plasma or whole blood in vitro. C-reactive protein (CRP) is a kind of acute phase protein, and it is one of the first known acute phase proteins in history. The increase of serum or plasma concentration is caused by the release of inflammatory cytokines such as IL-6, which almost always shows the presence of inflammation. Since C-reactive protein is usually increased after bacterial infection, but not after viral infection, it is of great significance to determine CRP content in human blood to distinguish bacterial and viral infection.