A system for controlling the bed level of a fluidized bed independent of the density of the bed material using a minimum number of pressure sensors is disclosed. A pressure sensor is positioned at the base of the bed, at approximately eight feet above the distributor plate, and at one or more intermediate locations therebetween. The measurements from the foregoing sensors are selectively processed through the use of a specific logic arrangement to produce an output signal representative of the bed level of the fluidized bed.