The term kidney tumors includes a wide range of mutually distinct entities. The common division is on benign and malignant tumors. Benign kidney tumors include oncocytoma, angiomyolipoma, leiomyoma, metanephrithic adenoma, papillary adenoma, cystic nephroma and reninoma. Oncocytoma is a tumor of epithelial origin composed of oncocytes and is the most common of benign kidney tumors. Angiomyolipoma is a tumor of mesenchymal origin composed of three types of tissue, causing kidney bleeding more frequently than any other kidney tumor, and also its classical type is the only type of benign renal tumor that can be reliably diagnosed radiologically. Leiomyoma is a tumor originating from smooth muscle cells. Metanephritic adenoma is a rare tumor of epithelial origin and more often causes polycythemia than any other type of kidney tumors. Papillary adenoma is an epithelial lesion of tubulopapillary architecture. Cystic nephroma is a rare cystic kidney disease, belongs to a group of mixed mesenchymal and epithelial tumors. Malignant kidney tumors include: kidney carcinomas, Wilms tumor and secondary kidney tumors. Kidney carcinomas are adenocarcinoma derived from epithelial cells of the renal tubule and are the most deadly of all urogenital cancers. Wilms tumor is a renal neoplasm of embryonic origin and is the most common malignant kidney tumor in children. With the benign and malignant tumors that fall into primary renal tumors, secondary tumors are the most malignant neoplasms of this organ (four times more common than the primary ones), and at the first place is metastasis of lung cancer, then breast cancer and gastrointestinal tract carcinoma metastasis.