This paper addresses the problem of the bottom hole pressure (BHP) behavior of a fractured horizontal well in a fractal flow medium. A detailed step by step procedure for obtaining the semi-analytical solution is present. The proposed method is validated available by comparing previous analytical solution. Sensitivity analyses about the influential parameters including wellbore storage factor, fracture properties, skin coefficient, permeability modulus and horizontal wellbore length on BHP are investigated in detail. The fracture scale (fracture half-length, fracture width and fracture number) mainly affects the channeling flow from the non-fracture zone to the fracture zone. With the increase of the fracture scale, the intensity of the channeling flow decreases and its duration becomes shorter. The fracture fractal index does not affect channeling flow its appearing time and intensity, but its influence on typical curves is mainly reflected in the seepage stage of the fracture zone. The pressure and derivative curves gradually upward warp with the increase of time, and the upward warping amplitude increases with the increase of the fractal index. The advantage of this method is to incorporate well geometry (well storage factor) and reservoir structure (the fractal index). The findings of this study can help for better understanding of well test interpretation of fractal reservoir