By using of satellite water vapor imagery,the IR picture and conventional observation,the convective system on the edge of subtropical high in the east of Shandong Peninsula in 10 August 1998 was diagnosed.The results show that these factors,such as the upper week cold air intrusion,weaking and moving to the east of the northwest edge of subtropical high,the 850hPa wind convergence on the edge of subtropical high and the convective instable atmosphere structure over Shandong Peninsula,were beneficial to development of the convective system.The convective systems occurred both in the brightest area of the satellite water vapor imagery and in the wester end of the convective clouds of the IR picture.