The sedimentation of the approach channel and the water area of Temryuk port is an important problem that has recently attracted the attention of researchers and engineers. The object of the study is the influence of the extension of the east and west breakwaters of the port. An analytical method of forecasting lithodynamic processes for various extensions of protective breakwaters was used. To verify the results, an analysis of space images of the coastal zone was applied. The volumes of sedimentation of the sea part of the Temryuk port approach channel were determined; recommendations for the extension of breakwaters were given. The sedimentary layer in the Temryuk Bay has two demarcated zones, one dominated by silty material, and the other, coastal, by fine-grained sand. Therefore, to determine the total alongshore sediment flow, the movement of muddy and sand flows was determined separately. The west breakwater retains only a small part of the sand transported to the canal; the east breakwater also has an insufficient length. The majority of the sand passing in the west and east directions falls into the canal. After the extension of the east breakwater by 100 m, the sedimentation of sand will be due mainly to its arrival from the west side, and thus the maximum thickness of the sediment layer will be about 2 m. The extension of the east breakwater by 200 m does not lead to a significant improvement compared to the extension option of 100 m, therefore, to reduce the sedimentation, it is necessary to extend the west breakwater by 100 m as well. After the extension of the west breakwater, the flow of sand into the channel from the west side will be significantly reduced. Thus, after the lengthening of both breakwaters, the volume of sedimentation of the channel with sand will decrease from 55 to 15 thousand cubic meters per year. The main contribution to the sedimentation will continue to be made not by sandy, but by silty material.