Using the ground and sounding data of 21 years in Tongliao and Chifeng stations in the southeastern Inner Mongolia, the precipitation phases such as rain, sleet and snow of two stations are analyzed. As a result, the temperature characteristics at 850 hPa are relatively close when it sleets or snows at Tongliao Station. The temperature characteristics of the 850 hPa are relatively close when rains and sleets in Chifeng Station; the thickness between 850 and 700 hPa is similar when sleets or snows in Tongliao Station and so it is when rains or sleets in Chifeng Station. In the boxplot, the thickness between 850 and 700 hPa and the temperature of 850 hPa exhibits opposite superposition corresponding to three phase. The temperature discrimination indexes of 850 and 925 hPa for Chifeng are higher than those for Tongliao Station: 1.5 ℃ and 1.7 ℃ higher when it rains, and 2.4 ℃ and 3.8 ℃ higher when snows. Temperature statistical results show that the ground temperatures is 4.0 or more in Tongliao and 6.0 ℃ or more in Chifeng Station when it rains, and less than 0.0 ℃ for both stations when snows. The temperature is 0.0 to 4 ℃ in Tongliao (0.0 to 6 ℃ in Chifeng) when it rains, sleets, and snows simultaneously. Although there are large differences between the thresholds of two stations, the three kinds of precipitation phases are closely related to the thickness of the lower layer and the temperature of middle and lower layers, but have little relation to the temperature of the middle layer. It is showed that the thickness of the mid/low layers and the temperature of the lower layer determine ground precipitation.