Abstract: A multi-threads tracking method, a multi-threads tracking system for an operating system and an electronic device using the same are provided. The multi-threads tracking method of the operating system includes the following steps. At least two message queue access events among two threads and one message queue are intercepted. A thread identification, a process identification, an input value and a return value of each of the message queue access events are recorded. Based on a determination of a relationship among the thread identifications, the process identifications, the input values, and the return values of the message queue access events, an In-Process dependency among the threads and the message queue is established.