Abstract: By the well log，stratus and other geology information，the relation between system tracts and condensed section and the characteristics between condensed section and coal-forming are studied in detail based on the depositional stratus of late Carboniferous epoch-Early Permian of Luxi Area. Three results can be concluded. First，three sequences and 24 parasequences can be divided by the stratus of late Carboniferous epoch-Early Permian of Luxi Area. The depositional systems of condensed section consist of facies of barrier lag，platform lag and so on. The condensed section lies on the top of transgressive system tract，which is an upward-deepening short base-level cycle on the top of middle-term cycle. The sediments are mainly pelmicrite and deepwater mudstone，which has a long forming time and a lower rate. So they became a good reference horizon. The condensed section and the forming of coal have an important relation. There are essential differences between the condensed section of passive marginal sedimentary basins and epicontinental sea basins. The condensed section of epicontinental sea basins can be found in the basin. And the depositional sequences in different place are very similar in the same basin. The condensed sections of research area include the fourteenth limestone and carbonaceous mudstone in the 1st sequence，the tenth limestone and 16th coal in the 2nd sequence，the third limestone and 7th coal in the 3rd sequence. The beginning time of coalification is the time of maximum sea-level and is in accord with the beginning time of limestone. All of these can be explained by the transgressive event of coal-forming.

Key words: condensed section, sequence stratigraphy, system tract, Luxi Area, transgressive event coal-forming