It is one of the most common malignant tumors in the urinary system, accounting for 2% to 4% of all malignant tumors in adults, and its incidence is increasing year by year. The early symptoms of kidney cancer are not obvious, and nearly 30% of the patients are already in advanced stage when they are found, missing the best treatment time, which is the invisible killer in human body. Why do we need kidney preservation treatment? Up to now, surgery is still the most effective and basic method to treat kidney cancer, among which the most commonly used is radical nephrectomy. In recent years, with the improvement of people’s awareness of medical examination and the progress of imaging examination, the detection rate of “small kidney cancer” has been increasing, and the so-called “small kidney cancer” refers to the early kidney cancer less than 4 cm in diameter. In terms of surgery, “kidney unit preservation surgery” has basically replaced traditional radical kidney cancer surgery as the main treatment method for small kidney cancer. As we know, kidney is an important organ of human body, which plays an important role in urine production, metabolism and red blood cell renewal. Nephrectomy with preservation of kidney unit can completely remove the tumor lesion while maximizing the preservation of normal kidney function unit, which adds a guarantee for the patient’s future healthy life. On the whole, after removing one kidney, the kidney function of the opposite side will be more or less affected. Once the disease occurs in the opposite kidney or is imaged by other systemic diseases, the kidney function may be seriously threatened and many treatments may be restricted and interfered. There are also many less options for treatment. Especially for patients with isolated kidney cancer, double kidney cancer, kidney cancer on one side with severe renal insufficiency, and kidney cancer on one side with contralateral renal failure or patients with chronic kidney disease tendency, kidney unit preservation surgery is of great importance, as it can provide maximum assurance of kidney function reserve for patients and effectively avoid and reduce the risk of future renal insufficiency and uremia. Therefore, minimally invasive treatment for kidney cancer with kidney unit preservation is gaining more and more attention. What are the methods of renal cancer preservation minimally invasive treatment? Usually, doctors will decide whether to perform kidney unit-preserving surgery based on the size and location of the kidney tumor, the patient’s condition and personal experience. A large amount of evidence-based medical evidence proves that the efficacy of kidney unit preservation surgery is the same as that of radical nephrectomy, as long as the tumor can be completely removed and the tumor recurrence rate after surgery is not affected. At present, the mainstream methods of renal unit preservation surgery include surgical resection, cryoablation and radiofrequency ablation, etc. The specific method should be selected according to each patient’s own condition, operator’s experience and hospital equipment. Surgical resection can be performed through open surgery or laparoscopic minimally invasive surgery, and is suitable for patients with anatomic or functional isolated kidney, hereditary kidney cancer or bilateral kidney cancer, as well as patients with benign diseases in the contralateral kidney, such as stones, chronic pyelonephritis, or other diseases that may lead to deterioration of kidney function (such as hypertension, diabetes, etc.), and for patients with tumor diameter <4cm< span=""> or tumor diameter <7cm< span="">. 7 cm< span=""> of low-stage peripheral type tumor and single asymptomatic kidney cancer patients are recommended to choose first to preserve the kidney unit for surgical resection. Cryoablation is the earliest clinically applied temperature treatment method and is widely used. It rapidly reduces the local temperature by liquid nitrogen or argon gas and causes cell denaturation, disintegration and death through three processes of low temperature, freezing and thermal thawing to remove tumor lesions. Cryoablation of kidney cancer mainly includes open surgery, laparoscopic cryoablation and percutaneous cryoablation. Among them, percutaneous cryoablation is less traumatic than laparoscopic ablation. With the development of image guidance equipment, the ultra-fine cryoprobe has been successfully developed, which can preserve the surrounding normal kidney tissues and kidney function to the maximum extent and become the least traumatic treatment. The number and type of probes used intraoperatively depends on the site and size of the tumor, and multiple probes can be used simultaneously for larger tumors. The advantage is that for multiple renal tumor lesions, multiple lesions can be treated simultaneously in a single procedure and can be repeated multiple times. Radiofrequency ablation is performed by inserting radiofrequency ablation electrodes into the target tissue and generating heat energy through the tip to destroy tumor cells, mainly through ultrasound and other imaging-guided percutaneous route of radiofrequency ablation treatment or combined with open or laparoscopic procedures. The efficacy of radiofrequency ablation also depends on the size and location of the tumor, which is best for tumors ≤3 cm and peripheral tumors, and renal cell carcinoma located laterally and posteriorly is easier to operate than those located medially and anteriorly.