Abstract: Electromagnetic field generated by spark discharge is a potential cause for electrical equipment failure. This research focused on analyzing the electromagnetic wave at certain spots by building numeral model of electromagnetic pulse radiation around electric discharge through applying finite difference time domain （ＦDＴD） method. According to the analysis of discharge current pattern as well as experimental current signal, exponential oscillation damping law was established and simulated. In the experimental part, electric dipole sources by which spark discharge was produced were distributed with forced distribution method. The electric and magnetic field components at multipoint were obtained, analyzed and compared with analytical model. The result shows that the magnetic waveform has a similar rough stretch with discharge current wave. This proves that the current component has a significant effect on magnetic field in the near field area of spark discharge, which provides a theoretical support on detection and prevention of electric spark.