Abstract: In order to study the spatio-temporal evolution of dielectric barrier discharge (DBD) excited by sub-microsecond pulse in atmospheric air, a high speed camera of intensified charge-coupled device (ICCD) which has a short exposure time of ns magnitude was used to photograph the process of the discharge, both the conditions of single and continuous (500 Hz) discharges were carefully studied in this work. On the condition of parallel board discharge excited by sub-microsecond pulse, it was found that discharge was not uniform at the early stage of the discharge. The discharge reached a uniform state while the current reached the peak point. Discharge during the falling time of the discharge was more uniform than that during the rising time of the discharge, the intensity of the discharge emission light and the discharge current coincided with each other. The existence of second discharge depended on the applied parameters such as repetitive frequency and voltage amplitude. Second discharge of the DBD was observed obviously in the single discharge mode and it was more uniform than the first discharge, but in the continuous discharge mode, generally the second discharge was too weak to be measured.