Protein A mimic linear peptide ligand, HWRGWV, was discovered by screening a solid phase hexamer peptide library using radiolabeled Fc fragment of IgG. This ligand exhibited the ability to purify HIgG from mammalian cell culture supernatant mimic containing 10% serum (cMEM) with the purity and recovery of 95% and 98%, respectively. The chromatographic performance was comparable to that of Protein A and A2P. It was proved that the binding of IgG to HWRGWV, like the case for Protein A, was not affected by the absence of the glycans on the Fc portion. Neither Protein A nor Protein G, however, was found to compete with HWRGWV for IgG binding. The LTQ-MS data showed that the ligand bound HIgG through its CH3 domain located on the C-terminal of the heavy chains.