Hepatocyte growth factor (HGF), which is a potent growth factor as a trigger for liver regeneration, act as accelerator for growth of various cells not only hepatocyte but also epithelial cells, endothelial cells, and some of mesenchymal tissue. Several studies have reported that HGF had correlation with tumor progression. It also established that HGF enhanced the motility of various types of cells, induced morphogenesis and tubule formation, and controlled the immune response, and many researchers have studied using mice or rats. This kit is developed for determination of rat hepatocyte growth factor (rat HGF) for research purposes. Rat HGF can be determined quantitatively using the rat HGF standard solution supplied with this kit. This kit also cross reacts with human HGF but its cross reactivity is about 4%.