The third-generation semiconductor material α-Ga₂O₃ is widely used in high-power electronic devices owing to its wide bandgap and excellent Baliga figure of merit. Among many growth methods of α-Ga₂O₃, hydride vapor-phase epitaxy (HVPE) can meet the requirements of growth rate, quality, and cost in preparing large-scale α-Ga₂O₃ wafers. A three-dimensional numerical simulation of the α-Ga₂O₃ growth process in HVPE growth chamber with showerheads was conducted to systematically and effectively evaluate the effect of parameters on growth results. The orthogonal experimental method was introduced to analyze the growth parameters based on computational fluid dynamics (CFD) simulations. The results indicate that growth rate and uniformity are closely related to the substrate tilt angle, O₂ inlet rate, N₂ inlet rate, GaCl outlet dip angle, and structure of showerheads. This study proposes an optimized combination of parameters, providing a useful reference for achieving a balance between growth rate and growth uniformity of the epitaxial layer in actual experiments.