Antimony selenide (Sb 2 Se 3 ) consists of 1D (Sb 4 Se 6 ) n ribbons, along which the carriers exhibit high transport efficiency. By adjusting the deposition parameters of vacuum-deposited methods, such as evaporation temperature, chamber pressure, and vapor concentration, it is possible to grow the (Sb 4 Se 6 ) n ribbons vertically or highly inclined towards the substrate, resulting in films with [hk1] orientation. However, the specific mechanisms by which these deposition parameters affect the orientation of thin films require a deeper understanding. Herein, a molecular beam epitaxy technique is developed for the preparation of highly [hk1]-oriented Sb 2 Se 3 films, and the effect of evaporation parameters on the film orientation is investigated. It is found that the evaporation temperature can affect the decomposition degree of Sb 2 Se 3 , which in turn determines the vapor composition and film orientation. Additionally, the decomposition of Sb 2 Se 3 related to evaporation temperature leads to significant changes in the elemental composition of the film, thereby passivating deep-level defects under Se-rich conditions. Consequently, the Sb 2 Se 3 films with highly [hk1] orientation achieve a power conversion efficiency of 8.42% for the solar cells. This study provides new insights into the control of orientation in antimony-based chalcogenide films and points out new directions for improving the photovoltaic performance of solar cells.