Abstract: Under the guidance of tectonic slope-break theory, the types of tectonic slope-break in Nanmazhuang area of Raoyang Depression of Bohai Bay Basin and relationship between distribution of sand bodies and types are researched by using seismic and well log data. The genetic mechanism of lithologic oil and gas reservoir at tectonic slope-break in this area is also discussed. The results indicate that the types of tectonic slope-break in Nanmazhuang can be divided into three types according to faults basic characteristics and combined style, they are "comb-like tectonic slope-break", "broom-like tectonic slope-break" and "ladder-like tectonic slope-break". Different types have different control on distribution of sand bodies, but as a whole, main faults of tectonic slope-break and direction of sediment influx system determine forming location of sand bodies, and strike of main faults controls stretch direction of sand bodies. The tectonic slope-break zone is favorable and important for the formation of subtle oil and gas reservoir, such as lithologic reservoir.

Key words: Raoyang Depression, tectonic slope-break, tectonic style, sand body, lithologic reservoirs