Energy and exergy analysis of sea water pump which is used for the main condenser cooling at lower steam propulsion system loads on conventional LNG carrier is presented in this paper. By using the measured variables from the exploitation, it is presented different influences of pump used power on cumulative energy and exergy power inputs. Energy and exergy pump power losses are reverse proportional, while pump energy and exergy efficiencies are directly proportional to increase in pump load. The highest obtained pump energy efficiency amounts 59.61 %, while the highest obtained pump exergy efficiency amounts 60.25 %. From the viewpoint of efficiencies and power losses, it will be optimal that analyzed pump operates at the highest possible loads.