The Ussuri region, comprising both sides of the Wusuli River, i. e. the Nadanhada Range on the Chinese side, Sikhote-- Alin on the Soviet side and the Khan-ka (Xingkai) block situated astraddle the Sino--Soviet border, has long been aninteresting subject in the study of the geology of Asia. The study on the geologyof the region involves the reconstruction of the accretionary history of the East-Asian continental margin and the evolution of the Western Pacific Ocean. Theapplication of the terrane concept may help solve some problems that cannot besolved with the geosynclinal concept.Through a cooperative study of the tectonicevolution of this region in light of the terrane concept the Chinese and Sovietgeologists have made the following progress. (1) The Primorye region of the Far-East U. S. S. R. and the peri--pacificregion of Northeast China were formed by the collage of several allochthnous ter-ranes including the Bureja Jiamusi, Nadanhada--Bikin, Central Sikhote--Alin, Te-tyukhe and Khanka. The identification and range of the Khanka terrane are dis-cussed in this paper, and the Yanji region and the Primorye region are inferredto be the Permian active continental margin of the Khanka terrane. (2) A complete stratigraphic sequence of the Nadanhada Bikin terrane hasbeen established through a comparative study, and the time of collage of the ter-ranes is beleived to be Late Jurassic.