Mfumo wa kingamaradhi (kwa Kiingereza immune system) ni seti ya tishu za mwili zinazofanya kazi pamoja ili kukwepa ugonjwa. Mfumo huo unasaidia kiumbehai kutambua na kuzuia hatari kutoka nje kwa afya yake, kama vile virusi, bakteria na vidusia mbalimbali. Kumbe pengine mfumo wenyewe umeathiriwa na kwa sababu hiyo unashindwa kufanya kazi. Mfano mmojawapo wa ukosefu huo ni UKIMWI unaosababishwa na VVU. Mfumo huo ni wa zamani sana, kiasi kwamba uliweza kuwepo katika eukaryota wa seli moja tu, kabla ya wanyama na mimea kutofautiana. Fani muhimu ya sayansi inayochunguza mfumo huo inaitwa imunolojia. Kingamwili Janeway C.A et al 2001. Basic concepts in immunology, Chapter 1 in Immunobiology, 5th ed, New York: Garland Science. ISBN 978-0-8153-4101-7 "Inflammatory cells and cancer", Lisa M. Coussens and Zena Werb 2001. Journal of Experimental Medicine, 193 F23-26. "Chronic immune activation and inflammation as the cause of malignancy" K.J. O'Byrne and A.G. Dalgleish 2010. British Journal of Cancer. 85, 473-483. Janeway C.A et al 2001. Evolution of the immun system: past, present and future. 'Afterword' in Immunobiology, 5th ed, New York: Garland Science.