There is no saying which one is the most serious, chronic renal failure or kidney cancer, it needs to be decided according to the patient’s condition. Chronic renal failure may not have any symptoms in CKD1~3 stages, or only have weakness, poor appetite, back pain and discomfort; after entering CKD3b stage, the symptoms will be more obvious, and in CKD5 stage, various systemic diseases may appear, even endangering the life. Kidney cancer requires active renal care, dialysis and causative treatment, etc. Most of the kidney cancers are primary kidney cancers. Kidney cancer is mostly primary kidney cancer, which mainly refers to renal cell carcinoma, with typical manifestations of hematuria, pain in kidney area and abdominal mass. Early stage often has no obvious symptoms and is mostly found during examination. It is not sensitive to radiotherapy, so surgery, immunotherapy and targeted therapy can be considered. Multiple metastases in advanced stage will have poor therapeutic effect. Whether it is chronic renal failure or kidney cancer, patients should go to regular hospitals to evaluate their conditions and actively cooperate with doctors to prolong their life or improve their quality of life.