Lysozyme is an important antibacterial material, as effective food preservative. A number of lysozymes are found in nature such as egg white, where exists about 3.5% of egg proteins. In this study, carboxymethyl cation exchange chromatography has been used for separation of lysozyme. A simulation study by ASPEN was also performed for saving time and cost in chromatography purification experiments. Important parameters in experimental chromatography were sample loading amount, NaCl concentration, and pH of eluent. Simulation results were successfully fitted with chromatograms from experiments with change of parameters mentioned above.