Abstract: A cell level change control device for cellular mobile radio networks with more than one level of cells includes means for comparing the value of a parameter representative of the speed of a mobile station with a threshold in order to decide if it is necessary to command a cell level change when the mobile station is served by a lower level cell contained in a higher level cell or when a mobile station is served by a higher level cell and it is determined that the lower level cell contained in that higher level cell constitutes the best cell. The device determines the load of the higher level cell and varies the threshold in accordance with the load.