The present invention addresses the problem of providing an inhibitor of lymph node metastasis of cancer which can be applied to a broad range of patients and can be used in combination with chemotherapy (anticancer drug treatment), radiation therapy, etc. The present invention provides an inhibitor of lymph node metastasis of cancer having C-reactive protein as an active ingredient. The inhibitor of lymph node metastasis can be used in combination with chemotherapy (anticancer drug treatment), radiation therapy, etc.
