The Fenghuangshan Pluton in the north edge of the Daba Mountains, is a Neoproterozic intrusive rock unit in the northern margin of the Yangtze Block. This paper reports the LA ICP MS zircon U Pb dating of this pluton. The dating results can be divided into three phases: early phase (797 6Ma), middle phase (770 6Ma, 774 5Ma), late phase (755 6Ma, 750 13Ma and 743 6Ma), indicating multi phase magmatic activity in the Fenghuangshan Pluton. These magmatic activities were also widely recorded in the other Neoproterozoic complex rocks in the Yangtze Block, such as the Hannan and Huangling complex. The Fenghuangshan Massif recorded the regional extension rifting in the northern margin of the Yangtze Block during early Nanhuan Period, formation of which may be associated with the activities of mantle plume that lead to the breakup of the Rodinia supercontinent. This research has important significance in understanding the growth and reconstruction process of continental crust of the Yangtze Block and the breakup mechanism of Rodinia supercontinent.