Abstract: Dolomite is an important reservoir rock in the carbonate of the Lower Paleozoic,Tarim basin，in which dolomitization took place in (1)capillary concentration and seawater-seepage/reflux, (2)mixed-water, and (3)deeper burial compaction flow at late diagenetic stage.To develop related dolomitization genetic models contributes to understanding and predicting the distribution of dolomite in time and space, guiding the petroleum exploration.Dolomites occurred in different areas and different geologic time in Tarim basin showed different diagenetic mechanism, in which dolomitization of deeper burial compaction flow and mixed water at late diagenetic stage contributes more to the reservoir rock.Deeper burial dolomite with good pore space can form prolific reservoir.

Key words: Tarim basin, Early Paleozoic, Dolomitization, Reservoir, Origin, Mode