Shale oil reservoirs exhibit significant transverse isotropy with well-developed weak bedding, leading to complex borehole collapse and instability patterns that conventional analysis methods struggle to optimize for wellbore trajectory. This study proposes a method for calculating borehole collapse pressure in transversely isotropic shale oil reservoirs considering weak bedding. Building on this, the angle between the weak plane’s normal vector and the wellbore axis is considered, and an innovative equivalent density of collapse pressure hemispherical projection is constructed using the vertical plane of the weak plane dip direction as the projection surface. This projection visually represents the distribution of equivalent density of collapse pressure under varying well inclination and azimuth angles. The results show that when the well inclination exceeds 80° and the azimuth aligns with the weak plane strike, the wellbore axis nearly coincides with the weak plane, resulting in higher collapse pressure and the poorest wellbore stability. Conversely, when the well inclination is less than 30° and the azimuth is opposite to the weak plane dip direction, the wellbore axis is nearly perpendicular to the weak plane, leading to lower collapse pressure and optimal wellbore stability. However, when the weak plane dip angle is minimal, the equivalent density of collapse pressure is more influenced by the orientation of in-situ stress. Additionally, with the increase of the degree of formation anisotropy, the collapse pressure also increases, and the borehole is more prone to collapse failure.