We investigate the dynamical evolution of a parity-time ($mathcal{PT}$) symmetric extension of the Aubry-Andr{e} (AA) model, which exhibits the coincidence of a localization-delocalization transition point with a $mathcal{PT}$ symmetry breaking point. One can apply the evolution of the profile of the wave packet and the long-time survival probability to distinguish the localization regimes in the $mathcal{PT}$ symmetric AA model. The results of the mean displacement show that when the system is in the $mathcal{PT}$ symmetry unbroken regime, the wave-packet spreading is ballistic, which is different from that in the $mathcal{PT}$ symmetry broken regime. Furthermore, we discuss the distinctive features of the Loschmidt echo with the post-quench parameter being localized in different $mathcal{PT}$ symmetric regimes.
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