Breccias are widespread throughout the Xikuangshan antimony deposit, central Hunan. Breccias can be divided into syndepositional breccia, paleokarst breccia, fault breccia, and hydraulic breccia. The orerelated breccias in the Xikuangshan deposit are emphatically discussed in this study. On the basis of detailed field investigation and qualitative analysis for these orerelated breccias, the fractal parameters Ds for breccia’s particle size distribution, and Dr and Dl for breccia’s fragment morphology distribution are determined by quantitative description approaches using fractal geometry methods, and the formation mechanism of these orerelated breccias is finally discussed. It is revealed that breccias related to antimony mineralization in the studied deposit can be divided into calcitecemented and silicacemented breccias. Fragments of those calcitecemented breccias mainly consist of weaklysilicified limestone, but highlysilicified limestone constitutes the silicacemented breccias’ fragments. Based on qualitative analysis and fractal quantitative investigations, it is concluded that hydraulic fracturing is responsible for the formation of calcitecemented breccias. Besides hydraulic fracturing, the formation of silicacemented breccias is also affected by chemical dissolution of hydrothermal solution. Therefore hydraulic fracturing is the most important mechanism for the formation of those orerelated breccias in the Xikuangshan mining district.