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In order to reveal sequence boundary formation mechanism of large scale craton epicontinental basin and coal accumulation characteristics under paleogeographic setting of isochronous sequence stratigraphic framework, sequence stratigraphic framework and coal accumulation were analyzed for the Permo-Carboniferous of Benxi-Shanxi Formation in the eastern Ordos Basin. A total of four types of sequence boundary are identified, which are regional unconformity surface, transgressive direction turnaround surface (BTR) resulted from settlement difference of basin basement, and normal regressive erosion surface (NSS) , exposed surface (NES) , corresponding conformity surface (NCC) , and river erosion surface(FEU) resulted from compulsory regression, exposed surface (FES), corresponding conformity surface (FCC). Coal-bearing strata is divided into three third-order sequences and six fourth-order sequences. Authores find that cyclical changes of base level controls the occurrence of coal accumulation, coal-base depositional environment and basin basement subsidence rate during coal accumulation period controls seam thickness and continuity. Paleogeographic comprehensive coal accumulation model within isochronous stratigraphic framework is proposed. The results show that widely distributed thick coal seams form around II-type sequence interface and the largest regression surface (initial flooding surface) of I-type sequence; under the lagoon-tidal flat context, coal-center is located in the tidal flat depositional environment, whose remaining accommodation space is small; under the lagoon-delta-tidal flat context, coal-center is located in the tidal flat depositional environment, whose remaining accommodation space is moderate and basement subsidence rate is large; under the shallow river delta context, coal-center is located in the restricted sea and lakes and bays of the delta plain depositional environment, whose remaining accommodation space is large and basement subsidence rate is large. [ABSTRACT FROM AUTHOR]