Large passenger ships usually have multiple galleys to meet the needs of different passengers for delicious food. And each galley demands to be equipped with one or more exhaust fans. The galley therefore requires high exhaust air volume, correspondingly with high energy consumption of the exhaust fan. The galley hood is an important component of the galley exhaust system, which is used to collect water vapor and oil smoke generated by various equipment in the galley. At present, the galley on large passenger ships generally uses the hood for centralized local ventilation. This study analyzes the control technology of the exhaust system of the traditional galley hood on large passenger ships. A new design method of energy-saving exhaust control system is proposed for the galley hood based on the frequency conversion control technology and variable air volume control technology for fans, in order to address the disadvantages of high exhaust air volume and high energy consumption. Through experimental verification on a Ro-ro passenger ship, the air volume data of the galley exhaust fan in the traditional exhaust system are compared and analyzed with those in the energy-saving exhaust system. It is verified that the new galley hood exhaust system has significant energy-saving effect and can be popularized in other ship types.