The present study undertaken to predict the three dimensional structure and active site analysis of inducible serine protease inhibitor -2(ISPI -2) known to inhibit the activity of entomopathogenic fungi Metarhizium anisopliae in Galleria mellonella a severe pest of most economic important crops. This inhibitor completely inactivates serine protease produced by M.anisopliae which acts as major virulent factor for G.mellonella and imparts natural immunity to the pest. Initially, the structural template for G.mellonella – ISPI-2 was identified from structural database using homology modeling or comparative modeling approach. Based on the knowledge of the template, a three-dimensional model was predicted and processed in to energy minimization, Ramachandran plot analysis, quality assessment and finally deposited into Protein Model Database. An active site of the theoretical model was analyzed and helpful to recognize the effective ligands.