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The behavior of fluid flow through rock fractures in the form of radial flow is a critical issue in various subsurface geological engineering projects. Previous work has considered to couple the radial seepage flow and the normal stress on the fracture surface, while ignored the influence of the fracture surface morphology on the seepage. Therefore, to quantitatively assess the fracture morphology influences on radial permeability, we conducted research adopting seepage testing and fracture surface scanning experiments and the tests results were present in this paper. The difference about fracture surface morphology of each sample can be quantitatively described by fractal dimension. Compared with natural fractures, artificial fractures had larger fractal dimension, rougher surface, and lower radial permeability. And the average radial seepage flow of natural fractures was about 1.57 times that of artificial fractures. In the same sample, the single hole permeability of different outlet holes was also different, which was related to the fracture surface morphology and its fractal dimension of the section line in this direction. The magnitude of fracture radial seepage flow increased with decreasing fractal dimension, and the change law of both followed a negative exponential function. A similar change tendency appeared in both artificial fracture samples and natural fracture samples. [ABSTRACT FROM AUTHOR]