A multi-cluster processing system and a method of operating a multi-cluster processing system are provided. The multi-cluster processing system includes: a first cluster including a plurality of first-type cores; a second cluster including a plurality of second-type cores; and a control unit configured to monitor loads of the first-type cores and the second-type cores, wherein when utilization of at least one of enabled first-type cores exceeds a predetermined threshold utilization of each of the first-type cores, the control unit enables at least one of disabled first-type cores in a first mode, and the control unit enables at least one of the disabled second-type cores and disables the first cluster in a second mode, wherein an amount of computation per unit of time of each of the second-type cores is greater than an amount of computation per unit of time of each of the first-type cores.