This paper provided a summarized review about the lightning nowcasting development of Beijing Meteorology Observatory. It then introduced the lightning nowcasting system currently being used in Beijing region, which consisted of lightning detection and nowcasting algorithm. Integrating data from LDAR (Lightning Detection and Ranging), radiosounding and Doppler radar, the lightning nowcasting system was formed based on thunderstorm echoes recognition using artificial neural network and thunderstorm tracing algorithm. The system enabled automatic lightning nowcasting in Beijing region. This paper also provided analysis on the forecasting ability of the system and its limitation.