Abstract: This paper summarizes the ideas and methods of Professor Wu Mianhua's diagnosis and treatment of prostate cancer based on the theory of "solidifying the root and clearing the filth", and believes that prostate cancer is a combination of deficiency in the root and excess in the manifestation, with deficiency and excess mixed. Spleen and kidney deficiency and cancer toxicity accumulation are the basis of prostate cancer, and the mutual entanglement of dampness, phlegm, heat and stasis is the key to the pathogenesis of prostate cancer. Clinically, prostate cancer is diagnosed and treated from the perspective of "solidifying the root and clearing the filth", warming the kidney and nourishing the kidney to consolidate the innate root, strengthening the spleen and activating the spleen to cultivate the acquired root, clearing heat and dampness, resolving phlegm and removing stasis to clear filth and detoxify. Strengthen the root to promote clearing the filth, and clear the fifth to help strengthen the root, achieve dynamic balance, and synergistically control the progression of tumors.