Abstract: A complete terrigenous sequence in fault－depressed lacustrine basin can be divided into four systems tracts：lowstand systems tract(LST)，trangressive systems tract(TST)，highstand systems tract(HST)and regressive systems tract(RST) In the steep slope zone of fault-depressed lacustrine basin，the development of source beds，reservoirs，cover rocks of hydrocarbon has specific and genetic relationship with systems tracts in terrigenous sequence，and different styles of terrigenous sequence can form different assemblages of source beds，reservoirs and cover rocks．In Biyang fault-depression the most favorable source rocks are the mudstone of semi-deep or deep lake facies in HST(belonging to regional hydrocarbon-producing formation)，and in next order the mudstone of lake facies in TSTand RSF (belonging to local hydrocarbon-producing formation)；The favorable reservoirs are distributed in sandstone body of fluvial fan-fan delta，and in slumping gravity flow fan body of delta slope gone．The regional cover rocks are mudstone of deep lake facies in HST, but the mudstone of lake facies in TST and RST can also form local cover．Synthetically considering plenty of geological factors such as：(1)stragigraphic stacking styles and strafigrapbic fray-out styles；(2)regional hydrocarbon-producing formations and cover rocks，and local hydrocarbon-producing formation and cover rocks；(3)several important and special sealed surfaces(e．g the top and bottom of sequence，downlap surface，basin-margin boundary fault，etc.)，and according to the types and characteristics of reservoirs in terrigenous sequence，the play types in terrigenous sequence of the steep slope zone of fault-depressed lacustrine basin can be generalized into three types ，eight subtypes and ten kinds．They include lithological up fray-out play type，lithological down fray-out play type，lithological facies change play type lithological lens play type，stratigraphic unconformity play type，stratigraphic trocation play type，stratigraphic overlap play type，stratigraphic downlap play type，stractural-lithological composite play type．Structural-stratigrapltic composite play type. The distribution of play type in every systems tract of terrigenous sequence is not balanced，and the most popular in TST，popular in RST and HST，the least popular in LST．From the spatial distribution regularities of play types in every systems tract of terrigenous sequeqce．the play types in TST age distributed in the transitional belt from basin borders to basin centers.Their buried depth is moderate．They are relatively close to source area．Thus，TST is a significant target to hydrocarbon exploration in the step slope zone of fault-depressed lacustrine basin．