pre-Neogene paleosols can reveal paleoenvironment during geological times. Paleosols were identified by field morphological, micromorphological, geochemical features, and so on. Currently, paleosols are classified based on taxonomic classification of modern soils, i.e, such indices as diagnostic horizons and diagnostic features, in conjunction with bulk chemical properties of paleosols etc., were employed to sort paleosols. By using paleosols, the history of ancient paleoclimate change might be reconstructed while variation of atmospheric pressure of oxygen and level of carbon dioxide concentration during pre-Cambrian and post-Cambrian periods, as well as paleoecological, paleogeographic features and paleolandscape were rebuilt. However, several problems should be tackled, e.g. establishing an extensively acceptable paleosol classification system, eliminating diagenetic effects on the properties of buried paleosols, and improving the research on the mechanism of paleoclimate information recorded by paleosols and its interpretation, etc. The further studies on diagenetic effects on the properties of buried paleosols and the elaborate relationship between modern soils and pedogenetic environment should be intensified.