Heat shock protein (HSP) 70 has been investigated from various aspects in experimental studies, since it is the most abundant form of HSP in cells. HSP 70 is involved in response to various acute and chronic insults of kidney and also other parts of the urinary tract. Although it is not a specific biomarker for any of the kidney diseases, HSP 70 level of body fluids may be beneficial as a biomarker in some specific circumstances, for example for the differential diagnosis of "a children with fever". The number of possible diseases in this situation is limited and an infection is most likely to be the reason of fever. Additionally, clarifying the exact role of HSP 70 in different kidney diseases enables to discover new therapeutic options in order to prevent renal fibrosis and chronic renal failure in the future. This chapter reviews experimental and clinical studies to find out the opportunities to utilize HSP 70 in daily clinical practice.