Abstract: In this paper, a method of mapping ray motions in three-dimensional (3D) enclosed space is proposed, and a ray-tracing algorithm is used to describe the paths of ray propagation in a rectangular space or 3D stadium model. The ray chaotic characteristic is discussed by using Wolf method to calculate the largest Lyapunov exponents (LLEs) of the ray systems in the rectangular space and the 3D stadium model. By comparing the ergodicity of position and direction in the two spaces, the effect of geometry on sound field uniformity is explored. The study shows that the 3D stadium model is a hyper-chaotic structure with two positive Lyapunov exponents (LE), in which the ray has the ergodic characteristics of position and direction, whereas the rectangular room is a regular one, in which the ray only has the ergodic characteristics of the position rather than the direction. The acoustic uniformity is evaluated by the difference of the sound pressure levels (SPLs) at different positions in the sound field by using Odeon room acoustics software. The results show that the geometry has significant effect on acoustic field uniformity.