Abstract: The extant Guangdong flora should be treated as a relict of Late Cretaceous or Early Tertiary floras, which has endured a long history of geological development. The fossil plants were very rich in different strata of geological age, such as Bennettites, Baiera, Ginkgo, Cycas and Gigantopterides, etc. Meanwhile from the Late Cretaceous to Tertiary stratum of Guangdong (and SW Guangxi), ample plant fossil( or pollen fossil) were also found, such as Celtis, Betula, Carpinus, Pinus , Abies, and Cedrus ,etc., accompanied by features of broad leaved trees and needle leaved trees, all of them being indisputably related to the geological history of Guangdong. Thus it naturally indicated that they probably originated from subtropical mountain regions, or it may be traced back to Cretaceous, or earlier, and Guangdong was undoubtedly one of the cradles of the Cathaysian flora or the flora of East Asia.