A new herbal composition. HemoHIM, was developed using irradiated animal models and was successfully applied as an immune-improving agent. In a view that the protection and recovery of immune, hematopoietic and self-renewal tissues are essential for radioprotective agents, HemoHIM was developed based on a novel combination of three edible herbs (Angelica Radix, Cnidii Rhizoma. Paeonin Radix) that meet all those requirements. HemoHIM significantly protected the immune and hematopoietic system and enhanced their recovery in y-irradiated mice. For the application of HemoHIM as a health functional food and a supplementary agent for the cancer patients, the efficacy of HemoHIM to improve the immune functions was further evaluated in immune-depressed animals and humans. Animal studies demonstrated that HemoHIM significantly improved the immune functions in cyclophosphamide-treated mice, aged mice, and dexamethasone-treated mice. In human studies, HemoHIM enhanced the immune activity and cytokine secretion in sub-healthy volunteers, and alleviated the severe leukocyre depression in cancer patients during radiation and chemotherapy. Based on these results, HemoHIM was approved by Korea FDA as a material of health functional food for immune function improvement and will be commercially available soon. This case of HemoHIM research and development suggested that irradiated animals can be good models for biological degenerations such as immune depression, self-renewal tissue damage, and aging for the development of biological modulators.