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This paper presents a k- turbulence model for simulation of steady current and itsinduced vortex shedding caused by the presence of an offshore pipeline. Performance of the modelaround a circular cylinder above a wall with gap to diameter ratios of 0.1, 0.35 and 0.5 underdifferent flow regimes with Reynolds numbers of 1500, 2500 and 7000 is studied. The flow field iscomputed with solving the Reynolds Averaged Navier-Stokes equations (RANS) the seabed underpipeline is treated as a plane boundary with no-slip boundary condition on pipe surface. Thegoverning equations are solved using Finite Volume Method in a Cartesian coordinate system.Based on the numerical solutions, the flow field, vortex shedding and distribution of shear stressdue to the presence of the pipeline near seabed are studied. In addition the mechanism of vortexshedding with different gap to diameter ratios is examined with focusing on the effect of vortexshedding on bed shear stress. It is found that the k- turbulence model can well predict the flowfield and its induced vortex shedding around a pipeline hence it can be easily applied forsimulation of scour below an offshore pipeline.