Defined  “Spore-Pollen Relative Density” as the number of spore-pollen per cover-glass, it makes full use of existing non-quantitative analysis data of spore-pollen, to study palynofacies or the source rock relationship with spore-pollen. Analysis of the data in same depths from Borehole Niu 28 shows that the curves of the spore-pollen relative density and of the actual spore-pollen content are similar. By taking the Paleogene system in the Dongying Sag, Shandong Province for an example, spore-pollen relative density and its application in petroleum geology are discussed.