A gravity flow deposit system discovered in the late Mesozoic strata of Lingshan Island in Qingdao has aroused dispute over its genetic environment. After emphatic observation of Zaochuanchang(Dockyard)，Dengta(Lighthouse), Qianceng Cliff（Mille-Feuille-liked Cliff）, Yangjiao Cave, Laohuzui(Tiger mouth) and Beilaishi(flying stone) sections, it has been discovered that the late Mesozoic outcrops in Lingshan Island is dominated by fine grained sandstone/mudstone of varied thicknesses ,volcanic lavas and volcanoclastic rocks intercalated with volcanoclastic depositional rocks and intrusions, and the strata occurs as a regression sequence with shallowing upward water; soft depositional deformation structures with varying types, scales and stages are developed in the strata like soft depositional deformation folds, boudinages, load structures, fiamme structures and soft dual structures; the late Mesozoic clastic deposits in Lingshan Island are primarily composed of sandy slumps and sandy debris flow deposits during transportation and sedimentation of sandy mass and secondarily turbidite deposits, overlain dominantly by terrestrial delta front deposits; the genetic mechanism behind these deposits should be mass transport deposition and turbidite deposition that took place at the lake delta front when deposits were supplied in plenty and at certain slope gradient, coupled with seismic actions and volcanic activity. Preliminary research shows that the paleoslope at that time struck SE-NW.