In this study, we proposed a design methodology for a ladle with flow characteristics that minimize air entrapment and oxidation during the pouring of molten aluminum in the casting process, and experimentally analyzed how filling behavior affects the porosity and mechanical properties of the cast product. To confirm the validity of the proposed ladle design, we performed a numerical analysis based on the solution algorithm for transient fluid flow to investigate mold filling behavior using the proposed ladle. We fabricated a ladle based on the design, and gravity cast the test specimens. Computed tomography was used to analyze the effects of the ladle’s pouring characteristics on porosity. Tensile tests were performed to evaluate the mechanical properties of cast specimens. The designed ladle reduced casting porosity and improved the mechanical properties of the cast product.