<p>The human body harbors a vast array of microorganisms. Changes in the microbial ecosystem can potentially lead to diseases, including cancer. Traditionally, research has focused more on the gut microbiota and its influence on cancer. However, with the advancement of sequencing technologies, scholars have discovered that microorganisms within kidney tissues are significant components of tumor tissues. Intratumoral microorganisms may affect tumor growth and development through certain mechanisms, influence the function of immune cells, or impact the effectiveness of chemotherapy or immunotherapy in patients. This paper reviews the latest progress in the research on intratumoral microorganisms in renal cancer (RCa). It summarizes the types and distribution characteristics of these microorganisms, discusses the close association between specific viral infections (such as HPV and EBV) and RCa, and highlights the role of microorganisms in the pathogenesis of RCa. This review provides new perspectives for understanding the pathogenic mechanisms of RCa, thereby offering potential clinical applications.</p>