The main adaptable response to increased temperature is heat shock response resulting in induction of proteins called heat shock proteins (HSP). They are present in all cells under proper growth conditions and they create 5-10% of the whole protein contents. HSP were divided into five basic groups according to their approximate molecular mass, expressed in kDa and called respectively: HSP 100, HSP 90, HSP 70, HSP 60 and small HSP. Heat shock proteins can act like antigens in many infectious diseases. Immunological response against proteins from HSP 60, HSP 70 and HSP 90 families was observed in diseases caused by bacterial and protozoan pathogens. It is known that ischemia and reperfusion activate HSP genes transcription in heart cells of various experimental animals. Human and Chlamydia pneumoniae HSP 60 were found in patients with stable coronary disease. Hence many researchers connect the increase of ischaemia with the passed infection caused by Chlamydia pneumoniae, which can influence the origin or development of atheromatous plaque in the vascular wall. HSPs play an important role in hyperthermic therapy commonly used together with irradiation. Moreover, works on the possibility of HSP application to delay of disease process in neurodegenerative diseases, such as Parkinson or Alzheimer diseases are conducted. The paper presents characteristics of heat shock proteins, role in the state of health and disease and possibilities of their usage in monitoring and/or treatment of diseases, e.g. cancers.