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Early Paleozoic volcanic rocks in Nuomuhong area occurred as basalt slice and meta-volcanic slice. SHRIMP zircon U-Pb dating of the basalt slice and the meta-volcanic slice show that the age of the basalt slice is 419±5 Ma, and that of the meta-volcanic slice is 401± 6 Ma. These ages directly testify that there existed Early Paleozoic ocean-continent transform in East Kunlun, the basalt slice was formed in an extensional mid-ocean ridge setting and the meta-volcanic rock slice was formed in an extrusion subduction and collision setting. The inherited zircon age of 1734 Ma in volcanic rocks reflects that the base of East Kunlun may be Middle Proterozoic.A great deal of practical data in recent years have proved that the East Kunlun orogenic belt and even the China central orogenic belt are complex orogenic belts that underwent polycycle orogenic evolvement [1][2][3][4][5][6][7] . Each orogenic cycle has left a compositional print, the multi-period ophiolites [4][5][6] and various types of tectono-magmatic production in the same orogenic belt. There is a suite of shallow metamorphic volcanic rocks in the Nuomuhong area in the east part of the East Kunlun orogenic belt. There exists disputation for its forming time all along. Previous study reveals that the volcanic rocks were composed of two different slices, namely basalt slice and meta-volcanic rock slice. Volcanic rocks of these two slices are obviously different in composition and tight intergrowth with meta-peridotite, pyroxenite and siliceous rock, and composed of typical ophiolite. So the determination of these volcanic rocks is very important in investigating early ocean-crust transform processes and tectonic evolution history of the East Kunlun orogenic belt. This paper reports the zircon SHRIMP dating of these two slices and discusses their geological significance.