Abstract: When students learn the relativity of simultaneity of special theory of relativity, they are easy to raise a question about the ideal experiment of the relativity of simultaneity. This essay raises this problem and uses the knowledge of time-like and space-like events to calculate and analyze it, and uses Miukowskian space to describe it geometrically to answer the question clearly and visually. Moreover, it makes a conclusion on judging the chronological order of events can be reversed or not.

Key words: special theory of relativity, relativity of simultaneity, time- like and space- like events, Minkowskian space