The Devonian's section in Nanguan area of Jinghong, southwestern Yunnan, which clearly showed continue transfbrm from flysch to molasese dimentary formation.There are continental resource and volcanic clastics in the sediments, and it this area had been happened orogeny with volcanic eruption action during Middle-Late Devonian . The discover will provid some useful new evidence for understanding geotectonic evolution of southern Lancangjiang Valley.