Abstract:Plenty of sporo-pollen fossils were found from the Upper Subformation of Hekou Formation at Chaijiatai, Lanzhou of Gansu, Minhe Basin. The sporo-pollen assemblage of the upper stratum of the Upper Suhformation was named as Schizaeoisporites-Cicatricosisporites. It could be further divided into two subassemblages. The upper one was Classopollis-Schiza- eoisporites, and the lower one was Piceapollenites-Cicatricosisporites. By analysing the periods of the important species and genera in the assemblage and comparing with the known assemblages in various districts, the author cosidered that the geologic age of the assemblage was the late phase of Early Cretaceous (Aptian-Alhian). The age of the second subassemblage was later which was Albian. So far, the stratum where the sporo-pollen fossils assemblage were found was the uppermost one of the Lower Cretaceous that have been found in Minhe Basin.