A method and a system for monitoring the operational state of a pump including acquiring a set characteristic diagram of the pump, the characteristic diagram of the pump being defined by a functional relationship between a first pump operating parameter characteristic of the operational state of the pump and a second pump operating parameter characteristic of the operational state of the pump. Subsequently, an actual characteristic diagram of the pump is acquired when the pump is installed in a higher-level system, in particular an aircraft system, and is running. Finally, the actual characteristic diagram of the pump is compared with the set characteristic diagram of the pump.