Hydraulic fracturing is a key preconditioning approach in block caving mining of hard-rock metal mines. The existence of natural fractures in orebody tend to result in an uncontrolled spatial propagation morphology of hydraulic fracturing. To understand the hydraulic fracturing propagation law within copper orebody with natural fractures, a finite element numerical model embedded with pore pressure cohesive elements was established using ABAQUS, and hydraulic fracturing behaviors was simulated under variable natural fracture lengths and density conditions. Results show that the length and density of natural fractures lead to a positive effect on the propagation morphology and propagation law of fractures. The natural fracture length has an exponent relation to the propagation radius of artificial fractures, while the density of natural fractures shows a linear relation with the propagation radius of hydraulic fractures. Regarding low in-situ stress difference, with the increase of natural fracture density, or with the increase of natural fracture length, the propagation radius of hydraulic fracture is larger. However, in terms of sparse density or short length of natural fractures, natural fractures will be expanded and branch fractures will appear. The numerical simulated hydraulic fracture propagation responds to natural fractures in hard rock mass is beneficial to oriented hydraulic fracture design.