Abstract:The carbonatite-type Mo-U polymetallic deposits in eastern Qinling are mainly composed of Huayangchuan U polymetallic deposit, Huanglongpu Mo deposit and Huangshuian Mo deposit. The Huayangchuan is a super-large U-Nb-Pb deposit accompanying rare-earth elements, and the Huanglongpu is a unique Mo deposit with large scale in the eastrn Qinling molybdenum belt. In this paper, we use molybdenite Re-Os dating and LA-ICP-MS monazite U-Pb dating to precisely determine the timing of the carbonate-type Mo-U polymetallic mineralization in eastrn Qinling. The Re-Os dating of molybdenite samples from Dashigou Mo deposit yields a Re-Os isochron age of 221.3±8.4 Ma. The LA-ICP-MS monazite U–Pb dating in carbonate dyke from the Qinlinggou Mo deposit and the Huayangchuan U polymetallic deposit yielded Tera-Wasserburg concordant ages of 207±11Ma (MSWD=3.7, n=38) and 222.5±6.7Ma (MSWD=1.8, n=37), respectively. These ages show that U polymetallic and Mo mineralization in carbonates were formed in Late Triassic. In conclusion, the Huanglongpu Mo orefield and Huayangchuan U polymetallic deposit which occurred in carbonatites were formed in the same mineralization series. The ore-forming materials of carbonatite-type Mo-U polymetallic deposit may derived from the mantle, and the carbonatites may be the products of the post-orogenic extensional setting in the Qinling Orogenic Belt.