To provide a fuel supply device in which a connection part of a fuel supply pipe and a fuel injection valve is not easily damaged due to stress.

The fuel injection device 1A is provided with the fuel supply pipe 2 supplying fuel from a fuel tank and a plurality of fuel injection valve 3 connected to the fuel supply pipe 2 severally. The fuel injection valve 3 includes a cylinder body 10 in which a fuel passage 12 is formed, a valve means 13 arranged in the cylinder body 10 and opening and closing the fuel passage, and an electromagnetic actuator 14 driving the valve means 13. The fuel supply pipe 2 is formed by joining two divided parts of an upper supply pipe part material 4 and a lower part supply pipe part material 5. The lower supply part material 5 and each cylinder body 10 of the plurality of fuel injection valves are formed as one body.