Hydraulic fracturing has been utilized as a pre-conditioning method in block cave mining to improve cavability and fragmentation sizes in recent years. A successful hydraulic fracturing operation depends largely on the interaction between natural fractures and hydraulic fractures. This process has been extensively studied in the oil & gas industry where hydraulic fractures are commonly vertical planar types. In this case, the effects of natural fracture dip angle and vertical in-situ stress are neglected. However, in block cave mining, hydraulic fractures are generally horizontal radial types. The applicability of the existing conclusions for block cave mining needs to be examined. In this paper, the interaction between natural fractures and horizontal radial hydraulic fractures is investigated by theoretical analysis and numerical modeling. It indicates that both natural fracture dip angle and approach angle influence the interaction result, as well as all the three in-situ stresses. It shows that hydraulic fractures are more likely to cross natural fractures if rock tensile strength is sufficiently low, or the product of flow rate and fluid viscosity is sufficiently high. Rock masses in block cave mining have mixed-qualities. High flow rate and fluid viscosity are recommended in regions where hydraulic fractures are not able to cross natural fractures.