Several processes which produce synthesis gas from natural gas have been analyzed by the exergy method. To minimize the exergy losses associated to chemical reaction, it is important to manage the exergy losses through the analysis, reconsidering the chemical path. A generally applicable and schematic way of performing exergy analysis and dealing with their results are illustrated. It is integrated to the modified flowsheeting reformer. As petrochemical industry in Indonesia, PT. Pupuk Sriwijaya II Palembang uses natural gas as a raw material to produce synthesis gas through the primary and the secondary reformers in a series. In the modified flowsheeting reformer, partial oxidation process has been added before the primary reformer and the secondary reformer has been eliminated from the process pathways. The exergy method of analysis has been implemented for each process, in order to calculate the exergies of the material streams along with the energy and mass-balance calculations both in the modified flowsheeting reformer and in a series process of the primary and the secondary reformers. And, the results of the calculations of the modified flowsheeting reformer in the process proposed modification are then compared to the results of the calculations of the series process of reformers in the existing conventional process. From the analysis, the overall exergy losses in a series process of the primary and secondary reformers can be reduced until 61.33, by applying the modified flowsheeting reformer. Copyright © 2011 Curtin University of Technology and John Wiley & Sons, Ltd.