| Eastern Tianshan Mountain lies between Kazakhstan plate and Tarim plate, its geologic structure is extremely complex, and mineralization condition is advantageous. On basis of some predecessors' correlative study, the metallogenic settings are analyzed in the area during late Paleozoic Era in this article, by studying the characteristics of stratum and the chemical composition of magma. The main conclusions are as follow:(1) The analysis of stratum's characteristics indicated that the Devonian and Carboniferous showed the characteristic of arc island-oceanic trench. The early Permian demonstrated the sedimentary characteristics of extension environment; this area's environment transferred from Arc Island into continental deposit in Late Permian.(2) The analysis of chemical composition of intrusive rock indicated that the eastern Tianshan entered into the collision stage in Late Devonian, it was in extrusive environment in Carboniferous, and had a conversion from extensive environment into relaxed from Late Carboniferous to Permian.(3) The analysis of petrochemistry of volcanic rock indicated: the volcanic rock in Devonian showed characteristics of calcium-alkaline-sodium series and arc island rock; in Carboniferous, the tectonic setting of the area was very complicated, that was, not only the volcanic rock which formed in arc-shaped archipelago (IAG) and mainland arc (CAG) but also formed in collusive belts were all existed. The volcanic rocks in Permian showed characteristic of postorogenic.(4) The analysis of tectonic stress environment of tectonic units indicated: the volcanic rock in Devonian belonged to calcium-alkaline-sodium series, arc-shaped archipelago of Paleozoic, and it was at the crushing stress condition; two of three group's acidic volcanic rock's elements in Carboniferous were in tension stress, the one was in extensive environment.
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