The use of in-filled columns is a new trend in composite construction industry. The bearing capacity is more than the sum of individual load carrying capacity of the stainless steel tube and concrete. In this paper the austenitic stainless steel tube of 304 grade is used. The conventional concrete is replaced by using geopolymer concrete as an infill material. A stainless steel tube of various thickness is used as a major parameter in this experimental investigation. The behavior of infilled stub column and hollow stub column is studied experimentally by applying gradual load along with analytical study using finite element software ANSYS. The design strength of the composite stub column was predicted by carrying out numerical investigation using various international codes. The ultimate load carrying capacity of the infilled stub column was calculated by experimental and analytical work and the results of the same were compared for numerical simulation. The results based on strength parameters were directly proportional to the thickness of the material used. © 2006-2018 Asian Research Publishing Network (ARPN).