An accumulator fuel injection system for a diesel engine is provided which is designed to facilitates easy maintenance of an injector and may be used in different types of engines. The accumulator fuel injection system includes generally an injector, a solenoid valve for controlling injection timing, a connector supplying the power to the solenoid valve, a fuel supply pipe connection, and a fuel supply passage. The injector is installed in the engine to have an injector head disposed outside an engine head cover. The solenoid valve is disposed within the injector head eccentrically with the longitudinal center line of the injector. The connector is mounted on the injector head. The fuel supply connection is arranged opposite the injection nozzle across camshafts of exhaust and intake valves of the engine. The fuel supply passage is formed in a side wall of the injector head of said injector.