Single-link cluster is introduced into mine microseism monitoring from a seismology point of view. The changes in spatial correlation length of mine microseismic events at different spatial scales are analyzed, and the underlying mechanisms are explained. The results show that large-energy microseismic events often occur after the spatial correlation length drops to a low value when the spatial scale is large. The larger the energy of microseismic events is, the more obvious the law is. Large-energy microseismic events occur after the spatial correlation length exhibits the power-law growth phenomenon, when the spatial scale becomes small. The smaller the spatial scale is, the more obvious the law is. The reason for this property is that microseismic events exhibit the space aggregation phenomenon before a large-energy microseismic event occurs, resulting in decreases in spatial correlation length when the spatial scale is large. By contrast, when the spatial scale is small, the spatial correlation degree of regional microseismic sources is high. Small-energy microseismic events occur gradually with concentration in low-intensity regions, and a large number of small cracks are produced before a large microseismic event occurs. The microseismic source is dispersed again once the regional stress is released. The entire system achieves a critical state. There is small cracks coalescence at a particular moment, which triggers a large-energy microseismic event. Therefore, it exhibits the phenomenon of power-law growth of the correlation length before the occurrence of the large-energy microseismic event. Moreover, statistical analysis of the bond length and frequency of SLC is performed. The result is that three non-scale ranges are identified. The turning points of the first two nonscale ranges are 180 m and 240 m, respectively, while the turning points of the second and third non-scale ranges are both approximately 450 m. The difference between the first turning points is due to the artificial disturbance, while the second turning point is affected by the geological environment.