Abstract: The energy efficiency of ships plays a significant role in the field of fuel consumption reduction and sea environmental protection now a days. The International Maritime Organization (IMO) has a mission to ensure all ships both new ships and existing ships realiable operation in shipping transportation system. Hence, the Energy Efficiency Design Index (EEDI), Energy Efficiency Operational Indicator (EEOI) and Ship Energy Efficiency Management Plan (SEEMP) are energy efficiency measures that control technical measure and operational measure. In this research, the operational measure tool is referred as a main key to solve the energy efficiency of ships in operational activities. Energy Efficiency Operational Indicator (EEOI) is a main objective to conduct this research. The reduction of fuel consumption of engine and limitation of exhaust gas emissions from ship operational activities are equivalent to reduce the Energy Efficiency Operational Indicator (EEOI) value. Bulk carrier is chosen to express and collected the experimental data in aims with verifying the results collected. The optimization of experimental data of bulk carrier with certain name M/V NSU JUSTICE 250,000 DWT of VINIC shipping transportation company in Vietnam which is conducted in this research in order to increase the energy efficiency of ships. Taguchi optimization method is used to carry out this optimization throughout empirical operation of M/V NSU JUSTICE 250,000 DWT. The most suitable orthogonal array L₉ was selected to determine the optimal experimental data of M/V NSU JUSTICE 250,000 DWT and to analyze the effects of these parameters. The proposed method has been discussed with Grey Relational Analysis (GRA) method for optimization of ships energy efficiency management. The study results will solve issue concerning about energy efficiency of ships as well as make an initial basis for next reseaches in the future.