Mitochondria are intracellular organelles with a variety of vital functions, including the provision of energy in the form of adenosine 5′-triphosphate. Increasingly, we are becoming more aware of the importance of mitochondrial dysfunction in a number of common medical conditions. In this review and overview, we focus on the growing evidence that mitochondrial dysfunction is involved in either the etiology or underlying pathophysiology of a broad spectrum of renal diseases, including acute renal injury due to ischemia-reperfusion injury, renal Fanconi syndrome, and glomerular disorders such as focal segmental glomerulosclerosis. In addition, mitochondrial dysfunction may also contribute to the growing burden of chronic kidney disease seen in our aging population, which is still largely unexplained. Unfortunately, at present, our ability to diagnose and treat renal disorders related to mitochondrial dysfunction is limited, and further work in this field is needed.