To give less influences of a change in fuel pressure on combustion due to the operation of a pressure limiter valve during the malfunction of a high-pressure pump.

This fail safe control device comprises a malfunction determining means for setting a threshold value between the opening valve pressure of a pressure limiter valve 6 and a target fuel pressure based on the operated condition of an engine and determining the malfunction of a high-pressure pump device 1 when the fuel pressure in an accumulator pipe 2 reaches the threshold value; and pressure reducing control means for controlling the reduction of the fuel pressure in the accumulator pipe 2 by opening a closed valve oil chamber 8 via driving means in the range of an invalid injection time for a fuel injection valve 3 for escaping a fuel in the closed valve oil chamber 8 to a low pressure side when the malfunction of the high-pressure pump device 1 is determined.