The effects of the casting design and reduced pressure in a flask on the mold filling of a molten aluminum alloy in the expendable pattern casting (EPC) process were investigated experimentally. An aluminum alloy plate was cast using the EPC process, and the arrival times of the molten metal were measured for three coats with different permeabilities. The use of a high permeability coat, or the condition of applying reduced pressure, led to a higher melt velocity. The melt velocity did not increase in proportion to the coat permeability. The experimental values for the arrival time of molten metal were compared with the calculated values based on the mold filling model used in the previous study. The values were in relatively good agreement except for when the coat permeability was very low. The arrival time in top pouring was almost the same as that in bottom pouring, except for when the coat permeability was very low. The melt velocity in the top pouring did not drop, even when the coat permeability was low.