Algae have been regarded as very useful materials for the research of eukaryote evolution, plant origin and evolution, and biogeographic changes. Thus, their diversity profiles are essential in understanding life's origin and early evolutionary development and exploring the earth's geology and geomorphology structure. We studied the terrestrial algae of Shibing Yuntai Mountain (SYM) and Chishui Danxia (CD) in Guizhou, the two world natural heritage sites in China representing dolomite karst and danxia landforms, respectively. G-F diversity index, similarity index, and Bray Curtis were used to compare their species composition. The results indicate that:(1) the algae are abundant in both heritage sites, featured with dominant cyanobacteria species, especially the families of Chroococcaceae and Oscillatoriaceae. The SYM, however, is rich in Scytonemataceae and Nostocaceae, with more abundance of Gloeocapsa and Chroococcus, which is different from CD with abundant genus Gloeocapsa. (2) SYM's G-F diversity indices are greater than CD's. Thus, the species diversity of SYM is higher than that of CD. This phenomenon may be related to the factor that the alga-promoting effect of the dolomite soil and the alga-suppressing effect of the red layer soil containing rich Fe and Mn. The predominance of nitrogen-fixed cyanobacteria in Scytonemataceae and Nostocaceae reflects the dolomite karst's environmental characteristics:rich in calcium and magnesium but poor nutrition. The species of Gloeocapsa in CD are more abundant, which are related to the silicate minerals in sandstone, besides the dry and hot climate. (3) The algae analyzed in both sites have significantly tropical and subtropical compositions and are endemic to China, especially regarding SYM. The similarity coefficients of families, genera, and species between the two sites are 56.25%, 44.05%, and 37.62%. Family similarity reaches a moderate level. The Bray-Curtis results show that the two sites are clustered into the same category despite their different geological and geomorphological features. The shared similarity at family and genus levels of the algae implies that the two sites maybe have diverged from the same aquatic environments. However, the heterogeneity at the species level between the sites maybe have resulted from their different terrestrial geographic landscapes, which shaped the algae alternatively under natural selection and environmental adaptation principles. We find the characteristic algae that can prove the landform's development from different compositions of the existing algae at the two sites. Thus, this preliminary study integrally and systematically analyzes terrestrial algae's diversity, heterogeneity, and similarity, and geographic varieties in evolutionary development, stratigraphic lithology, and structure of the two heritage sites in China.