A method and an apparatus for determining a to-be-migrated task based on cache awareness in a computing system having multiple processor cores is disclosed. In the method, the computing system determines a source processor core and a destination processor core according to a load of each processor core. Through respectively monitoring the number of cache misses of each task and the number of executed instructions of each task in the source processor core and the destination processor core, the computing system obtain an average cache miss per kilo instructions of the source processor core and an average cache miss per kilo instructions of the destination processor core. Then, the computing system determines, according to the obtained average cache miss per kilo instructions of the source processor core and the destination processor core, a task to be migrated from the source processor core to the destination processor core.