Diandongosuchus is an extinct genus of poposauroid pseudosuchian from the Middle Triassic of China. The type species Diandongosuchus fuyuanensis was named in 2012 from the Falang Formation of Yunnan Province. It is a marine species of pseudosuchian that shows similarities with another Chinese Triassic species called Qianosuchus mixtus, although it has fewer adaptations toward marine life. It is the basal-most member of the clade Poposauroidea.