A pressure fluctuation control device for controlling the pressure fluctuation in the upstream side of a common rail in an accumulator injection system, the device comprising: a high pressure pump comprising a plurality of cylinders in which fuel oil is pressurized to a certain level of high pressure, and a check valve that is provided at a fuel outlet of each cylinder so as to open and close the fuel passage of the check valve; a common rail that accumulates the pressurized fuel oil delivered by the high pressure pump; and a fuel injector that is provided at each cylinder of the engine so that a prescribed amount of the highly pressurized fuel oil accumulated in the common rail is injected into each cylinder of the engine through the fuel injector; wherein the pressure fluctuation control device further comprises: a secondary common rail that is connected to the fuel outlet of the check valve corresponding to each cylinder of the high pressure pump; and at least one injection pipe that connects the fuel outlet of the secondary common rail to the common rail, the number of injection pipes being smaller than the number of check valves corresponding to the cylinders of the high pressure pump, characterized in that the accumulation volume of the secondary common rail is smaller than or equal to the accumulation volume of the common rail, and in that the throttle area regarding the outlet side of the secondary common rail is smaller than the throttle area regarding the inlet side of the secondary common rail such that delivery pressure fluctuations regarding the high pressure pump as well as surge pressure vibrations regarding the check valves are prevented. a high pressure pump comprising a plurality of cylinders in which fuel oil is pressurized to a certain level of high pressure, and a check valve that is provided at a fuel outlet of each cylinder so as to open and close the fuel passage of the check valve; a common rail that accumulates the pressurized fuel oil delivered by the high pressure pump; and a fuel injector that is provided at each cylinder of the engine so that a prescribed amount of the highly pressurized fuel oil accumulated in the common rail is injected into each cylinder of the engine through the fuel injector; wherein the pressure fluctuation control device further comprises: a secondary common rail that is connected to the fuel outlet of the check valve corresponding to each cylinder of the high pressure pump; and at least one injection pipe that connects the fuel outlet of the secondary common rail to the common rail, the number of injection pipes being smaller than the number of check valves corresponding to the cylinders of the high pressure pump, characterized in that the accumulation volume of the secondary common rail is smaller than or equal to the accumulation volume of the common rail, and in that the throttle area regarding the outlet side of the secondary common rail is smaller than the throttle area regarding the inlet side of the secondary common rail such that delivery pressure fluctuations regarding the high pressure pump as well as surge pressure vibrations regarding the check valves are prevented. a secondary common rail that is connected to the fuel outlet of the check valve corresponding to each cylinder of the high pressure pump; and at least one injection pipe that connects the fuel outlet of the secondary common rail to the common rail, the number of injection pipes being smaller than the number of check valves corresponding to the cylinders of the high pressure pump, characterized in that the accumulation volume of the secondary common rail is smaller than or equal to the accumulation volume of the common rail, and in that the throttle area regarding the outlet side of the secondary common rail is smaller than the throttle area regarding the inlet side of the secondary common rail such that delivery pressure fluctuations regarding the high pressure pump as well as surge pressure vibrations regarding the check valves are prevented.