Abstract: By using squall line data of new type weather Radar in Dehong,Yunnan,and contrasting with 5other squall line cases at the same time,some mesoscale indicators of squall line weather in low latitude plateau are obtained.By analyzing characteristics of echo intensity,echo velocity field,air stream distribution,surface wind velocity in squall line weather in2006-07-17 in Dehong,the results shows: upper and low-level jet stream is important factor causing squall line severe weather;parameters such as central intensity of strong Radar echo,height of top,etc.can be used as indicators of tendency now cast because of good correspondence with weather process.The velocity of surface wind can be better estimated according to Bernoulli's equation:Δp/ρ=ΔV2/2,but influences of topography and squall line direction should be considered.By combining with Radar precipitation retrieval and data of high density precipitation stations in Dehong,conclusions can be drawn that almost the whole heavy rain region is caused by stationary stratiform cloud echo about 25—40dBz in its rear part.