By the effect of the Super Typhoon “Ramasun” in July 2014，the counties in Dehong Prefecture suffered from the rainstorm, heavy rainfall appeared in the river basins of Irrawaddy and Salween, particularly at 6:00 on July 21, 2014. The flash floods, landslides and debris flow occurred in Mnghai, Mangshi City. Analysis of the storm flood ，storm rainfall and the concerned disaster characteristics is helpful to understand the characteristics of the rainstorm floods in the region, which provide the basis for flood control and disaster prevention[1].