In order to improve the directional accuracy of the pitch angle of solid array, the localization equations of an acoustic array using solid five-element are derived. Previously used to calculate the elevation angle with sine, but this method is not conducive to describe the influences of both the two structure dimension parameters on the accuracy of elevation angle. Aiming at the situation, on the elevation angle calculate use the tangent value. Compared the localization ability with the traditional planar five-element array, find that characterizing the elevation angle using the tangent can gain a higher directional accuracy, and at the same time can describe various factors that affect pitch angle accuracy more accurately. The solid five-element cross array has good performance, and engineering application value.