The river is called Río Negro from its sources in the highlands of Huehuetenango and El Quiché until it reaches the Chixoy hydroelectric dam (located at 15°16′54″N 90°29′27″W / 15.281536°N 90.490952°W / 15.281536; -90.490952 (Chixoy Hidroelectric Dam)), where the Río Salamá and Rio Carchela converge with the Río Negro.

After the Chixoy dam, the river is called Río Chixoy and flows northwards, marking the departmental limits between Alta Verapaz and El Quiché, until it reaches the border with Mexico.

The Chixoy river's water discharge of 551 cubic metres per second (19,500 cu ft/s) is Guatemala's highest.

This was one of the main reasons for selecting this river for the construction of the Chixoy Hydroelectric dam.

Guatemala's National Institute for Electricity (INDE) is planning the construction of another hydroelectric dam on the Chixoy river.