To provide an accumulator fuel injection system for a diesel internal combustion engine, having an auxiliary accumulator and a connection body for implementing an injection characteristic with good responsiveness, improving output and fuel economy of a diesel engine and reducing harmful components, and sufficiently securing a space for the auxiliary accumulator or a space for incorporating engine components.

The accumulator fuel injection system for a diesel internal combustion engine comprises: a nozzle holder for fuel injection disposed for each cylinder of the diesel internal combustion engine; a common rail accumulating pressure of fuel supplied to the nozzle holder; a high-pressure supply pump supplying high-pressure fuel to the common rail; a fuel distribution pipe connecting the common rail with the nozzle holder; and a fuel supply pipe connecting the common rail with the high pressure supply pump. The auxiliary accumulator is disposed downstream of the common rail, and the connection body is disposed downstream of the auxiliary accumulator.