Abstract: Objective To explore the clinical characteristics of clear cell renal cell carcinoma (ccRCC) patients with renal sinus or perirenal fat invasion,and analyze the prognostic factors. Methods From December 1,2012 to August 9,2019,patients with ccRCC confirmed to invade renal sinus fat or perirenal fat by pathology in the First Medical Center of Chinese PLA General Hospital were identified and followed up.Univariate log-rank test and multivariate Cox proportional hazards regression analysis were performed to identify risk factors related to all cause death. Results Totally 174 patients were identified,with average age of 58.1±11.4 years old,among whom 29 were females and 145 were males.Within a follow-up period of up to 86.1 months,136 patients survived and 38 died,with 25% quantile survival of 50.62 months.Log-rank test showed that tumor diameter,invasion site,presence of venous tumor thrombus and Fuhrman nuclear grade significantly affected overall mortality (all P<0.05).Multivariate Cox model revealed the tumor diameter ≥6.8 cm (HR:3.94,95% CI:1.78 to 8.71),perirenal fat invasion (HR:0.33,95% CI:0.12 to 0.91) and presence of venous tumor thrombus (HR:2.06,95% CI:1.00 to 4.26) were independent prognostic factors. Conclusion Tumor diameter ≥6.8 cm,renal sinus invasion and presence of venous tumor thrombus are independent influencing factors for negative prognosis in ccRCC patients with renal sinus or perirenal fat invasion.