The Zaibian mafic intrusion is located in the transition zone of the Yangtze Block and the South China fold system, where is the southwest of Jiangnan orogenic belt. The major elements results show that the samples belong to the calc-alkaline series, with the feature of poor K₂O (0.03%~0.29%). The REE results of the samples show that the samples enrich LREE, with a higher total REE, and a weak or no Eu and Ce anomaly. The LILE (K, Ba, Rb) is tens times higher than MORB relatively, which is consistent with the intra-plate basalt. The HFSE is mid to weak of Nb. The study supports the view that South China was located in the supercontinent Rodinia between the continents Australia and Laurentia in the Neoproterozoic.