By using the solenoid fields data of sea level pressure over Southern hemisphere,through the difference value fields and correlation analysis,the influence of general circulation of atmosphere over Southern hemisphere on precipitation over South China during preflood season have been analyzed.The results show that the general circuation of atmosphere systems over the Southern hemisphere are basically outofphase for drought and waterlogging years,in same term or earlier stage.The influence mechanism of Australia anticyclone,Mascarene anticyclone and convective active region of South America have been preliminary analyzed.The significant fact of the anticorrelation relationship between the Australia anticyclone intensity and SW monsoon in South Sea affecting South China have been researched for the first time.