The relationship between influenza and meteorological factors in Shenzhen is analyzed by using the detailed data of influenza cases and meteorological data from 2003 to 2007 in Shenzhen. The results show that spring and summer is the influenza epidemic period in Shenzhen, and the epidemic period is tending to move toward summer gradually; the seasonal variation has a close relationship with the temperature and humidity; the influenza peak occurs frequently in the case of temperature being in the range of 25 ℃ to 30 ℃ and higher humidity. The regressive equation for forecasting the clinical rates of InfluenzaLike Illness (ILI) is established. The minimum air temperature, minimum relative humidity and sunshine duration are the typical meteorological forecasting factors.