Using meteorological data and MM5 numerical simulation, the characteristics are analyzed for two heavy rain events caused by cyclone in Shandong Province. The upper-and low- layer system, horizontal and vertical distribution of equivalent potential temperature, vertical motion, and divergence are studied for the two heavy rains. The results show that in cool section heavy rain occurred behind the warm and moist tongue of 850hPa, it has apparent back slantwise structure, strongly baroclinic frontal zone, and stronger dynamic conditions; but in warm section heavy rain occurred in the warm and moist tongue of 850hPa. It provides an excellent reference for forecasting heavy rain.