A fuel injection system includes a fuel feed pipe for feeding fuel from a fuel tank and including upper and lower feed-pipe members joined to each other, and a plurality of fuel injection valves connected to the fuel feed pipe, each fuel injection valve including a cylinder having a fuel passage formed therethrough, a valve device arranged in the cylinder to open and close the fuel passage, and an electromagnetic actuator for driving the valve device. The cylinder of each fuel injection valve is integrated with the lower feed-pipe member.