With the increasing age of RV. Baruna Jaya III (30 years), the ships often face various problems. The continuous operation of the engine causes a decrease in its performance which eventually results in the failure of the main engine. For instance, damage to the main engine can stop operating of the ship at sea which eventually have various impacts on ship and life safety as well as operational cost. In this context, efforts to manage ships especially for the operation of main engine and its prevention from errors through real time monitoring and control system have become a major issue. This study aims to design a monitoring and alarm system for the main engine performance on the RV. Baruna Jaya III as the preliminary step for the development of the overall monitoring system. As a result, a design for data acquisition of the main engine performance parameters in real time and the design of a ship’s main engine failure alarm system have been developed using PLC-based design technology and a SCADA-based monitoring system. This system can be thus further built for the performance of the ship’s main engine, as part of management ship operations and maintenance policies.