A general way to enhance the sound absorption capability of polyurethane foam is the use of a nonplanar surface such as the pyramidal surface. The use of the pyramidal surface can greatly enhance the sound absorption of the foam in the mid and high frequency ranges. In this study, a three-dimensional finite element frequency domain acoustical analysis is used to analyze the normal incidence sound absorption of the pyramidal polyurethane foam. Such a numerical method is more efficient than the earlier studies by saving the calculation time on the elements of the incident acoustic field. In the study, the maximum broadband averaged normal incidence sound absorption of the pyramidal polyurethane foam is pursued based on the change of the pyramidal shape. The variation of the pyramidal shape is performed by changing the angle between two sides of a pyramid but keeping the pyramid base and the foam volume the same throughout the study. It is found that the pyramidal polyurethane foam with pyramidal angle of 29° has the highest broadband averaged normal incidence sound absorption in the 100–4k, 500–4k, as well as 2k–4k Hz ranges.