Magnetic stimulation as an efficient and non-invasive technique has been applied broadly in clinical practice. It is mostly used in determination of nerve centre motor conduct and evaluation of motor cortex excitability; in inspection of central nervous system function by measuring peripheral nerve conduct; and in study of pallium nerve distribution. These are conducted in an attempt to control brain activity and provide new methods for the diagnosis and treatment of some brain diseases. This paper reviews the physical theory and functional mechanism of magnetic stimulation, as well as the applications of magnetic stimulation in biomedical examination and treatment.