Based on the 300 000 DWT channel project of Lianyungang, this paper analyzes the feasibility of the utilization of ADCP walk-propelled method for suspended sediment measurement in muddy coast where the suspended sediment concentration is low, studies the law of diffusion of suspended material, which is caused by the dumping of dredged materials in the main navigation channel in Lianyungang harbor, and its impact on the siltation of the navigation channel in Xuwei harbor, the research result of which may serve as a reference for the improvement of the dredging operation in the 300 000 DWT channel in Lianyungang harbor.