Large scale oceanographic explorations are presently continuing around the Porcupine Seabight area, which is located towards the south-west Ireland. This area is an embayment of the north Atlantic continental margins. It's importance due to the dominant hydrocarbon resources are not unknown, and on-going experiments are important due to the involvement of higher order variability (in terms of physical and geological settings) around this area. Multi-beam angular backscatter study to characterize the eastern slope seafloor of the Porcupine Seabight is initiated first time. Backscatter data acquired from twenty-nine locations of the carbonate mounds and associated buried mounds (Belgica province), and channel seafloors like: Kings channel and Gollum channels are analysed in this paper. Processing details of the angular backscatter data was carried out to apply the scattering models to determine seafloor roughness. Employed normalization to the angular backscatter data to obtain shape invariant seafloor indicate distinct grey levels for mound, buried mound, and various channel seafloors (four distinct types of seafloors) within the backscatter dynamic range of 12 dB. The backscatter levels are the highest for the mound areas followed by the buried mounds, channel seafloor, and inter-channel areas. Present study was further substantiated by employing a semi-empirical method to determine the shape aspects of the area backscatter strengths. Estimated three parameters like: predicted 20( angular backscatter response, slope and coefficient of variations of the angular backscatter responses are computed to understand general seafloor characteristics of the varying area seafloor. The use of Helmholtz-Kirchhoff's angular backscatter theory which is a functional of the power law are carried out to estimate sea water floor interface roughness parameters. The sediment volume inhomogeneity parameters are also determined by use of curve fitting to the overlaying interface curves. Mounds, buried mounds, seafloor channels, and inter channel seafloor's are characterized and their details are investigated in this paper.