New helium isotopic data of ores and rocks from the Altay orogenic zone, Xinjiang,China are reported, which show that the pegmatites from No. 3 vein in the Keketuohai area have high ~3He/~4He ratios up to 1 .795 x 10~(-6) and 2.54 x 10~(-6). Such a result suggests that the metallogenic process of rare metal deposits in the Altay orogenic zone might be related to mantle degassing. New helium isotopic data of ores and rocks from the Altay orogenic zone, Xinjiang, China are reported, which show that the pegmatites from No. 3 vein in the Keketuohai area have high ~ 3He / ~ 4He ratios up to 1.795 x 10 ~ (-6) and 2.54 x 10 ~ (-6). Such a result suggests that the metallogenic process of rare metal deposits in the Altay orogenic zone might be related to mantle degassing.