Abstract: A functional failure of Rap1 as a molecule that regulates integrin adhesion is believed to be related to pathology of inflammation, allergy, autoimmune diseases, cancer immunity, transplantation immunity, and the like that are immune diseases, and therefore elucidation of the mechanism of regulation of integrin adhesion by Rap1 leads to an understanding of the pathology of these immune diseases and the development of their treatment methods. As a molecule that is involved in the regulation of integrin adhesion by Rap1, p30 has been identified, and it was found that the p30 regulates the Rap1 function by binding to it. The use of this knowledge can be used for developing a p30 and Rap1 binding inhibitor and the like, developing drugs for inflammation, allergy, autoimmune diseases, cancer immunity, transplantation immunity, and the like, and further elucidating their regulation mechanisms.