Abstract:It is suggested basic lava and intermediate lava constitute the volcanic rolcanic by the lithology and the testing of rare earth element in west Tianshan Mountains.They are all belong to calcic-alkalic series.Both of them have lower potassium and high sodium.The REE distribution patterns of the volcano indicate that they have a rich light REE.The curve is steep in light REE while relatively flat in heavy REE.All these characteristics reflect that the volcano was formed in the rift-valley environment.