The approach channel or navigation channel leading to harbour from offshore has significant impact on maneuvering operations of ships as well as on wave pattern/conditions at entrance of the harbour. The layout of an approach channel has gained prime importance since large capital dredging is involved which effects the cost economics of any port or harbour. The harbours located on an open cost are subjected to severe wave actions particularly during the monsoon season. The wave conditions inside the harbour, in the turning circle and at the entrance need to be within certain permissible limits to facilitate smooth berthing and maneuvering operations. The impact of approach channel and other structures on wave conditions and patterns must be properly studied by using suitable modelling technique. Physical wave models or small scale models are convenient tools of predicting full scale performance and help in better visualization and measurement of the effects of interactions of complicated wave patterns at the entrance and structures like berths, jetties etc. located inside the port area. The present study describes the role of approach channel in natural wave energy attenuation by using physical model for the case study of proposed Gateway Port at Kakinada under Kakinada SEZ in Andhra Pradesh. The layout of Gateway port consists of two breakwaters; North or lee breakwater 570 m long and South or main breakwater 2670 m long protruding in a depths of about (−) 9.0 to (−) 11.0 m. The proposed approach channel is 250 m wide and 4 km long leading upto (−) 20.2 m depth contour offshore. The alignment of approach channel in almost parallel ENE direction and it changed towards SE direction at 1.2 km from the tip of port breakwaters. The physical wave model studies were conducted at CWPRS by using a geometrically similar rigid bed model (Scale of G.S. 1/150). The physical wave model consists of a three dimensional model tray shallow wave basin equipped with the Random Sea Wave Generation (RSWG) facilities with SCADA control and multi channel data acquisition system. The physical wave model studies were conducted for three most predominant wave directions viz. and ENE (Hs = 1.5 m, Tp = 12 s), East (Hs = 2.0 m, Tp = 12 s) and SE (Hs = 3.5 m, Tp = 12 s). The large dredged depth of the channel and its width as well as channel curvature, slopes etc. have contributed significantly in wave height attenuation at the harbour entrance of more than 50% for the predominant directions.