Change of erosion and deposition of bottom bed in the estuarine and coastal areas is one of the main research contents of sedimentation dynamics, and field observation is the key to obtain accurately the information about changes of scour and silting of the bottom bed. For the in-situ measurement of bed elevation variations in the southern channel of the Yangtze River mouth, an Acoustic Doppler Velocimetry (ADV) instrument, which is used to observe 3D hydrodynamic information of near-bottom boundary layer, is applied. In order to verify the reliability of the measured data in the field, two indoor experiments are designed for verifying the feasibility of the bed elevation measured by using ADV: Experiment 1 is to determine the range of the bottom-bed elevation measured with ADV by comparing the distance from ADV transmitting transducer to bottom bed measured artificially H with that recorded by ADV itself h; and Experiment 2 is to determine the influence of sediment concentration on ADV measurements through measuring the static high turbidity water with ADV. The experimental results show that: ① The distance from the ADV transducer to the bottom bed can be directly acquired through the vhd data file stored inside ADV. However, the results thus measured require the actual height H between the transducer and the bed satisfying 150 mm≤H≤370 mm; ② When the actual height H between the transducer and the bed is less than 150 mm, the actual height H can be obtained by extracting the pck data file; ③ When the actual height H is greater than 370 mm, the instrument cannot obtain the value; and ④ When the sediment concentration exceeds 14.36 kg/m³, there is also no way to obtain the information about actual height H in the ADV measurement.