Asterias Fault Complex is present in the SW Barnets Sea and is extensional in nature. This fault complex separates the Hammerfest Basin in south from the Loppa High in northVariations in structural trend and frequency of deformation (associated synthetic and antithetic faults and related structures) warrant subdivision of fault complex from west to east as (i) the western segment (ii) the central segment and (iii) the eastern segment. The western segment is of particular interest because of related structural complexity and the associated antiformal feature. Previous models to explain deformational mechanism in western segment have been revisited, and a new model on the basis of new evidence on 3D seismic data is proposed. This model relates the deformation style in the western segment to extensional system comprising ramp-flat-ramp extensional faults.Degree of deformation associated with the fault complex decreases from west to east and the main boundary fault changes geometry from ramp –flat- ramp in western segment to downward concave in central segment and finally ends up as planar normal fault. 2D/3D seismic reflection data does not support the idea of Carboniferous / Permian rifting while Late-Mid Jurassic to Early Cretaceous is well registered in the study area. Asterias Fault Complex has been assigned the age of Late-Mid Jurassic to Early Cretaceous.