The lower part volcanics of the Maizi area, Altay,are composed of high Na rhyolit e with minor thoeiite—alkali basalt and trachyandesite, and volcanics in the up per part are mainly calalkalic rhyolite. They were formed in a reactiva ted belt on the continental margin.In the lower part, basalt was derived from th e transitionalenriche d mantle source, and rhyolite derived from the mantlecrust source. These magmas experienced fractional crystallization, magma mixing and immiscibilition. Rhyol i te of the upper part resulted from partial melting of the crust. The magma evolu tion is involved in contamination with the upper crust and sea water. The relationship between volcanics and Fe an d Pb Zn oreforming progress is also discussed in this paper.