The present paper focus on reduction of drag force behind a bluff body by using a passive method. Numerical simulations have been carried out for ten different isolated cylindrical geometries at a Reynolds number of 100. Influences of corner radii on the drag force behind a two dimensional bluff body have been investigated using ANSYS FLUENT. It was found that the critical radius at which the drag force turned to be minimum compared to the circular cylinder was R=D/3. The results in terms of the bulk parameters like time history of drag and lift coefficients, Strouhal number, recirculation length and contours of pressure, vorticity and streamlines have been discussed.