The deviation of micro-epicenter and macro-epicenter is an urgent task in the rapid judgment of earthquake intensity. This paper aims at studying the main area of earthquake rupture and mark the possible position of macro-epicenter through the research on aftershock energy field distribution within 24 hours after 7 strong earthquakes with MS6.5, so as to provide reference for emergency rescue. This paper takes the Wenchuan earthquake as a case study to illustrate how to make sure the magnitude of completeness, how to render the distribution chart of energy field and the calculation method of energy field, as well as how to determine the macro-epicenter. This paper then compares the estimated epicenter with the actual epicenter at each period of the 7 earthquakes and comes to the conclusion that：(1)At each period of the 24 hours after the catastropy, the macro-epicenter referred from aftershock energy field distribution could reduce the deviation referred from the estimates epicenter of micro-epicenter. (2)Estimated epicenter at the periods of 2, 4, 6, 12, and 24 hours after the quake could act as the correction factor of rapid judgment of earthquake intensity with the excellent effect in the period of 24 hours after the quake.