Fracture shear can induce flow channeling within the fracture plane, enhancing flow perpendicular to the fracture shear direction. The resulting flow anisotropy is crucial for determining optimal well locations at geothermal sites, where efficient heat extraction relies on productive fluid circulation. This research examines the impact of shear on flow anisotropy under variable conditions of normal stress, shear displacement, and fracture size. The research comprises three main stages: (1) simulating fracture shear incorporating asperity degradation, (2) modeling preferential fluid flow within a sheared fracture, and (3) upscaling the laboratory-scale results to the reservoir scale of a hundred-meter. Two fracture surfaces with dimensions of 10 × 10 cm and one fracture surface with a dimension of 1× 1m are used for analysis. A numerical shear model based on elastic-plastic contact mechanics is employed to simulate asperity degradation during shear. Flow simulation on a sheared surface reveal significantly increased permeability anisotropy ratio defined as the ratio of permeability perpendicular to parallel to the shear direction. This permeability anisotropy ratio still prevailed and even increased with higher normal stress, emphasizing the importance of considering flow anisotropy under high-stress conditions. The effect of fracture sizes is investigated using square fractures with side length from 10 cm to 60 cm, extracted from the 1× 1m fracture. While increasing fracture size led to higher permeability and reduced variation in flow anisotropy across the fractures, anisotropy remained evident and significant. To investigate the effect of anisotropy in reservoir scale, a hundred-meter scale reservoir model with an upscaled sheared fracture was constructed. Injection tests showed that higher flow rates were observed when injection and production wells were positioned perpendicular to shear. The results demonstrate that perpendicular flow is enhanced both at the laboratory and reservoir scale, highlighting the importance of considering the influence of fracture shear on flow anisotropy for optimizing well locations.