As an efficient and convenient method，water jet scouring technology has been widely used in deep sea engineering.The scour volume from a cohesive bed under a vertical submerged jet scouring has been studied.The contour embryo of scour volume was obtained by grouting method，and the scour volume of was evaluated by 3D scanning technology.Through indoor test，the relationship among jet velocity，impingement height，scour time and water content of mud sample and scour volume are explored：1）Scour volume decreases with the increase of impingement height.2）Scour volume increases with the increase of jet velocity.3）Scour volume increases with the increase of scour time，but gradually tends to balance.4）With the increase of water content of mud sample，the scour volume increases significantly.Finally，based on 54 sets of experimental data and dimensionless analysis，an empirical formula of scour volume is obtained，which may provide a reference for water jet trenching and water jet assisting pile installation in ocean engineering.