This paper presents the parametric study of single square perforated fixed ended LDSS (Lean Duplex Stainless Steel) flat oval section stub columns, by varying the square perforation size, location of perforation along transversely as well as longitudinally, using the Finite element software Abaqus (2009). Based on the Finite element study, a near-linear reduction in ultimate load capacity with perforation size has been observed. The reduction is found to be higher for the stockier cross-sections as compared to slender sections. The percentage drop in ultimate load capacity remains relatively unaffected for larger perforation when the section is slender and located at the flat element. It is seen that, in comparison to the slender section, perforated stocky sections showed a mild drop in ultimate load as the perforation is located toward the corner junction of flat and curve portion from the mid-flat region. Further, in general, it is observed that the reduction in load capacity to be highest when the perforation is located near the mid-height. A design approach based on modified ASDM (Automotive Steel Design Manual) has been proposed to estimate the design capacity of single square perforated flat oval LDSS hollow columns