This paper describes an application of direct drive volume control (DDVC) to ship speed control. The DDVC fuel injection device consists of an AC servo motor, a fixed-displacement oil-hydraulic pump, and an oil-hydraulic cylinder. The cylinder piston pushes a fuel pump to pressurize fuel and an injection valve opens to inject fuel into a combustion chamber. Timing and the quantity of fuel injection can be controlled by the electric signal added to the AC servo motor. In this paper, the DDVC fuel injection device is applied to engine speed control of marine diesel engine and ship speed control. A simulation model is made including a model of the DDVC fuel injection device, propeller model, and hull motion model. Firstly, engine speed control system is proposed. Stop injection angle is automatically adjusted according to engine speed error signal. Secondarily, ship speed control is proposed. Propeller pitch angle is used to control ship speed. Simulation study of these control systems are presented to show the capability of the DDVC fuel injection device for marine diesel engine.