Abstract: The structural evolution of Bayanhot Basin underwent a structural transform from compressional deformation to exten-sional deformation. So, a lot of structural types were developed in the basin. Normal fault and strike-slip fault all can be found in the studied area. According to the stress environment, the
structural assemblage types of Bayanhot Basin may be divided into two major types, six basic types, i.e. Compressional struc-tural assemblage, including imbricate thrust assemblage, trap-door structure, pop-up structure, assemblage of listric thrust and dragged anticline and dragged syncline; extensional struc-tural assemblage, including assemblage of listric normal fault,fault and roll over anticline and horst-graden assemblage. Trap-
door structure, pop-up structure, and assemblage of listric thrust, dragged anticline and dragged syncline are most favor-able to the accumulation of oil and gas.

Key words: Bayanhot Basin, anticline, syncline, struc-tural type, structural assemblage