We investigate the role of Hunds coupling in the spin-wave excitations of the ($pi, 0$) ordered magnetic state within a five-orbital tight-binding model for iron pnictides. To differentiate between the roles of intraorbital Coulomb interaction and Hunds coupling, we focus on the self-consistently obtained mean-field SDW state with a fixed magnetic moment obtained by using different sets of interaction parameters. We find that the Hunds coupling is crucial for the description of various experimentally observed characteristics of the spin-wave excitations including the anisotropy, energy-dependent behavior, and spin-wave spectral weight distribution.
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