Various types of structures are used in shore protection and littoral sediment trapping. Groins are one of these structures. The main hydraulic function of the groin is to control the long shore current and littoral sediment transport. In this paper, the effects of various groin parameters (length and spacing) and wave parameters (wave height, wave period and wave angle) on the accretion of the area protected by straight groin were studied in a physical model. The model studies were performed using regular waves in a basin. A numerical model which depends primarily on a CERC model is employed to examine the effects of some of the above parameters. Good agreement was found in the results of physical and numerical models. The results of a numerical model are compared with field data that were obtained by deep sounding measurements at Carsibasi coasts, Trabzon Province, Turkey. The important outcome from this study may be employed in designing of straight groins.