The co-effects of longitudinal and lateral freshwater runoff represent a particular plume to plume interaction (PPI) in the Lingdingyang Estuary. In order to study the estuarine dynamics and sediment transport discipline in the PPI area, field observations were implemented in the western area of Lingdingyang Estuary between 2015 and 2016 by combining the observation methods of shipborne full-profile observation and mooring observation tripod. Hydro-dynamic parameters such as water depth, flow velocity, salinity, temperature, suspended sediment concentration (SSC), erosion/siltation of the bottom seabed were recorded in deep channel and shallow shoal in the west part of Lingdingyang Estuary for complete tidal cycles during spring and neap tides in wet and dry seasons. Squared mean shear (S2), buoyancy frequency (N2), gradient Richardson number (Rig), bottom shear stress (τ), vertical fluctuant SSC flux (<SSC’w’>) and other microcosmic parameters for each measurement were well calculated. Erosion/siltation rate on the seabed shows a continuous siltation in the channel but a continuous erosion on the shoal during neap tide of wet season and a periodic erosion-siltation cycle on the channel and shoal in the rest tidal cycles. The SSC at the bottom of the deep channel shows a good correlation with the τ, while a poor correlation on the shallow shoal. All of these indicate an evident trap effect for the advective suspended sediment in the deep channel. As most of the advective suspended sediment silted in the seabed, the SSC is mostly formed by the resuspension process. While the advective part of SSC on the shallow shoal failed to silt or the remaining quantity is non-negligible compared to the amount of resuspension part, revealing a poor correlation between τ and bottom SSC. In order to further confirm the correctness of the results, recorded SSCs by mooring tripod were divided into an advective part and resuspended part by the local bottom erosion/siltation rate. A good correlation is then proved out between bottom bed shear stress and resuspended sediment concentration.