A statistical relationship between daily electricity depletion and meteorological elements in Beijing city is established by using the real power consumption data and meteorology data during the Summer of 1998 and 1999. Statistical and forecasting equations of daily power consumption including the maximum, the minimum and the average value are achieved, respectively. The results show that the power consumption had a very close relationship to the weather condition, especially it is very sensitive to the temperature, and then to the relative humidity, wind, sunshine duration and as well as the precipitation.