M.S. Elbe Maru is the first of large merchant vessels of triple-screw propulsion ever built. This paper presents the results of investigations into her qualities on propulsion, propeller cavitation, behavior in waves and maneuverability, through model experiments and sea trials on the actual ship. The results indicate that the triple-screw ship was successfully designed, and the M.S. Elbe Maru has given good performances in the time since her completion.