Abstract: The characteristics of main genetic facies and the types of sedimentary associations of Taiyuan Formation in Yanzhou Coalfield are expounded. The formation and distribution of the coal-rich unit and its relationship with the underlying genetic facies,as well as the influence of eustatic change of sea level on the genetic facies,and the evolution of the sedimentary system are analyzed. Using the marker beds the analytical elements (corresponding to the paresequences in the sequence stratigraphy) are divided, and taking the analytical elements as the basic untits for the analyses and mapping,the coal-accumu-lation regularities of the Yanzhou Coalfield are studied.