Based on the lightning data from 2000 to 2003, the temporal and spatial characteristics of lightning in Guangzhou are analyzed. It is shown that lightning occurs frequently from April to October with quasi-bimodal daily variation, most frequently from afternoon to midnight. Lightning occurs the most frequently in the urban area, secondly in the northeast part of the city. The positive lightning center is located to the south of the urban area. The related circulation patterns and synoptic systems are also studied. The synoptic patterns of severe lightning can be divided into three categories and six types, which are affected by the westerly trough, under the control of the subtropical high or related to tropical systems, respectively. The disposition of each type varies in different seasons.