Abstract: Multi-cellular organism fossils from Liangshan Formation of Paleoproterozoic Yimen Group in central Yunnan Province are special products of the co-evolution between early life on the earth and the environment in Great Oxygenation Event (GEO), or generalized Lomagundi Event. However, it is difficult to directerly determine the geological time when the multi-cellular organism lived, because of thegeneral lack of volcanic interlayer in Liangshan Formation and the perturbation of multi-period tectonic thermal events. In this paper, the authors accurately revealed that the multi-cellular organism lived 2.18~2.05Ga years ago, as shown by the 260 zircon grains isotopic testing results, from two incanus tuff samples at the top of Luowadie Formation and in Liangshan Formation respectively, an incanus silty tuff sample in Liangshan formation, two sallow calcareous silty tuff samples in Liangshan Formation, in Tongchang Township, Yimen County, in central Yunnan Province, in combination with regional tectonic thermal events analysis. This epoch is equal to that of multi-cellular organism, found in Franceville area, Gabonese Republic, Africa, suggesting that early important events on the earth had geological synchroneity.