The survey of submarine geology on western part of Sagami Bay was made, using the submerged surveying vessel “Shinkai”. The surface sediment on floor of depth of 100 m, off Ito, consists mostly of fine sand (Md=2.2φ). The deposit on head of canyon, depth of 400 m, is uniformly fine silt (Md=6.4φ). Bottom current on shelf was 30-40 cm/Fsec, but it on head of canyon had scarcely been measured. There were a lot of biota on bottom surface sediment, and the bioturbation of surface sediment was often observed on both of shelf and canyon. During submergence of vessel, a large number of suspended particles “marine snow” was observed.