The aim of the article is to analyse changes in the channel layout of the Piaśnica River estuary and the lithodynamic characteristic of bed deposits as a consequence of sea level changes. The analysis is based on the results of measurements in the river estuary conducted in the years 2014–2015. The data of daily average sea level were obtained from the Institute of Meteorology and Water Management (IMiGW) station in Władyslawowo and Łeba. The research documented distinct changes in the position of the riverbed. Analyses of textual indicators were conducted i.e. mean grain size (MZ), standard deviation (σI), skewness (SkI) and kurtosis (KG) were calculated according to Folk and Ward ormulas (1957) using the Gradistat software. Based on the abovementioned data conclusions were made about the changing conditions of the river sediment transport.