Lightning electromagnetic pulse is strong electromagnetic interference sources, along with the rapid development of information technology, it has all kinds of hazards of electrical and electronic equipment, communications equipment becoming more serious; interference with normal radio communications and a variety of remote control devices, and become radio an important source of noise; secondly, it is also harmful to the area around the lightning channel, and in the case of a lightning strike electrical equipment may affect the normal operation of power systems. To protect sensitive equipment from the dangers of lightning electromagnetic pulse field and select the appropriate protective measures, the paper analyzes the situation of the surrounding space radiation when lightning electromagnetic pulse propagation, by solving the Maxwell equations, using Matlab to draw the amount of space each lightning electromagnetic field Distribution. Distribution by ground lightning electromagnetic pulse in the earth study law, can get a variety of electrical parameters conclude the lightning current, lightning charge moment and charge distribution in the cloud, etc..They can provide a viable reference for positioning data and lightning warning.