The Gutenberg-Richter and Omori Laws, which are generally used to characterize the temporal distribution of aftershock, failed to reflect the statistic properties of climatic outbreak of aftershock energy. Based on a new concept of magnitude clusters describing the fluctuation of aftershock energy release of the Wenchuan Earthquake, we discovered that the pattern of the continuous high-magnitude aftershock follows a power-law rather than a non-Poisson distribution. This suggests that the after-shocks with high magnitudes are statistically clustered. We then divided the aftershock sequences into three sections and demonstrated that though the probability of strong outbreaks decreased with time, there exists a high possibility of the occurrence of isolated high-magnitude aftershocks in the future. Based on self-organized criticality theory, the mechanisms of the power-law pattern of magnitude clusters are discussed. This discovery may be used to guide future aftershock predication and the associated post-disaster reconstruction. The Gutenberg-Richter and Omori Laws, which are generally used to characterize the temporal distribution of aftershock, failed to reflect the statistic properties of climatic outbreak of aftershock energy. Based on a new concept of magnitude clusters describing the fluctuation of aftershock energy release of the Wenchuan Earthquake, we discovered that the pattern of the continuous high-magnitude aftershock follows a power-law rather than a non-Poisson distribution. This suggests that the after-shocks with high magnitudes are known clustered. We then divided the aftershock sequences into three sections and demonstrated that though the probability of strong outbreaks decreased with time, there exists a high possibility of the occurred isolated high-magnitude aftershocks in the future. Based on self-organized criticality theory, the mechanisms of the power-law pattern of magnitude clusters are discussed. This discovery may be used to guide future aftershock predication and th e associated post-disaster reconstruction.