On the basis of the definition and classification of terrestrial slope breaks, this paper discussed the genesis and sequence of slope breaks resulting from structure, sedimentation and erosion, especially subtle reservoirs controlled by lowstand systems tracts. The differences between terrestrial and marine slope breaks are:(1) the slope of a terrestrial slope break is steeper than a marine one, which is caused by structural movement and rapid terrestrial sedimentation from a close-by provenance; and (2) marine slope breaks are commonly mono-slope breaks, whereas terrestrial slope breaks are composed of several slope breaks. These were applied in the Dongy-ing Sag of the Bohai Bay Basin. We established a sequence framework composed of four sequences. These four sequences are all divided into lowstand systems tracts, advance systems tracts and highstand systems tracts. We also established the relationship between reservoirs and sequence units, especially lowstand systems tracts, and studied the types of sand bodies in systems tracts of terrestrial slope breaks and the mechanism for oil-gas reservoir formation.