Abstract: Quite a number of numerical computation works contributed to the atmospheric acoustic propagation emerging constantly in recent years make the formation of a new developing sub-branch "Computational Atmospheric Acoustics" become just round the corner. The present paper provides a brief, clear, systematic and comprehensive introduction to this brand-new field and gives a relatively exhaustive demonstration of its main objects and methods, especially the parabolic equation (PE) method, the fast field program (FFP) and the Gaussian beam (GB) approach-may be regarded as a modified ray tracing procedure. A discussion concerning the comparison among the results obtained by these various methods cannot be included for the limitation of space, some opportunity for publishing these interesting materials separately would be expected.