Currently, the incidence of most malignant tumors in China is still on the rise, and this is also true for kidney cancer. 2015 World Health Organization epidemiological survey data show that China has become the country with the highest number of new kidney cancer cases in the world each year. In China, due to the widespread use of medical screening in the past 10 years, more and more early kidney cancers are detected and found, while the surgical technology is improving, which makes the use of kidney-preserving surgery (partial nephrectomy) more and more widespread. The proportion of kidney cancer patients treated by kidney-preserving surgery in our center in the past 3 years is as high as 70%, which is one of the highest kidney-preserving rates in China, and many of them are complicated and difficult cases, such as tumors in the hilar region, completely endogenous tumors, multiple tumors, solitary kidney tumors and large volume tumors (including huge angiosmooth muscle lipoma with a length of more than 18 cm). Why should kidney preservation surgery be performed? First of all, the tumor control effect of kidney-preserving surgery and radical nephrectomy is comparable under the premise of ensuring the principle of tumor-free. Our center is one of the earliest medical units performing kidney-conserving surgery in China. Whether kidney-conserving surgery or radical nephrectomy is adopted, the tumor control effect of stage 1 and stage 2 kidney cancer is the same (the 5-year cure rates of stage 1 and stage 2 kidney cancer are 95.0% and 87.8%, respectively). Secondly, due to the high cure rate and long-term survival of patients with early stage kidney cancer (stage 1 and 2), the probability of renal insufficiency and even renal failure (uremia) in the sole kidney will increase significantly with aging and the possible emergence of related concomitant diseases (e.g. hypertension, diabetes, etc.). The appearance of the above-mentioned conditions will significantly reduce the quality of life, making the burden on each family significantly higher and consuming a large amount of social and medical resources. The 2015 European Association of Urology guidelines for the management of kidney cancer suggest that kidney-conserving surgery is superior to radical nephrectomy in limited kidney cancer (stages 1 and 2) based on recently obtained patient outcomes and quality of survival. Patients with kidney-preserving surgery scored higher in many aspects of quality of survival, whereas patients after radical nephrectomy were concerned about their health status because they had only one kidney. Patients with tumor diameter <4 cm and normal contralateral renal function had the highest quality of life scores after treatment, regardless of other factors.