A fuel pressure sensor/sensor mount assembly for use in a fuel injection system equipped with fuel injectors which inject fuel, as supplied from an accumulator through fuel pipes, into a multi-cylinder internal combustion engine mounted in an engine compartment of a vehicle. The assembly includes a connector unit and fuel pressure sensors. The connector unit has formed therein a plurality of communication paths each of which is to establish a connection between one of the fuel injectors and the accumulator through one of the fuel pipes. The connector unit also has formed therein sensor mounts exposed to the communication paths. Each of the fuel pressure sensors is disposed in the sensor mount to measure the pressure of the fuel in the communication path. This structure permits steps of installing the fuel pressure sensors within the engine compartment to be decreased and ensures desired measurement accuracy of the fuel pressure sensors.