A method and apparatus for migrating a task in a multi-processor system. The method includes examining whether a second process has been allocated to a second processor, the second process having a same instruction to execute as a first process and having different data to process in response to the instruction from the first process, the instruction being to execute the task; selecting a method of migrating the first process or a method of migrating a thread included in the first process based on the examining and migrating the task from a first processor to the second processor using the selected method. Therefore, cost and power required for task migration can be minimized. Consequently, power consumption can be maintained in a low-power environment, such as an embedded system, which, in turn, optimizes the performance of the multi-processor system and prevents physical damage to the circuit of the multi-processor system.