To provide a system for controlling a construction machine, which can be implemented inexpensively, can detect a failure in any of pressure sensors, controllers, an inverter device, and an electric motor for swing, and can secure safety and required workability for an operator. Redundant hydraulic pressure sensors 20, 21 provide input to a first controller 11 for calculating a swing command, and a second controller 22 provided in an inverter device 13 for controlling an electric motor 16 for swing. The second controller 2 detects an abnormality in any of the hydraulic pressure sensors 20, 21 and the first controller 11 by a process for determining the validity of a swing command signal, and allows the swing operation to continue by using a signal from the second hydraulic pressure sensor 21 when determination is made based on the contents of the abnormality that the electric motor 16 for swing can operate normally.
