<p>We present a systematic theoretical investigation of the linear polarizations of the fluorescence radiation of 5<i>s</i>_1/2 → <i>np</i>_3/2 (<i>n</i> = 2, 3, 4, where n is the principal quantum number) lines after inner-shell single-photon ionization of the exemplary Xe atoms and the Xe-like W²⁰⁺ ions by (polarized and unpolarized) incoming photons within the framework of the relativistic approach and density-matrix theory. The correlation between the polarization of the incident light and the polarization of the characteristic radiation is examined. The sensitive dependence of the transfer of the polarization of fluorescence radiation emitted by the photoionization of atoms/ions is thoroughly analyzed. Our results demonstrate that incident light polarization plays a critical role in determining the polarization of fluorescence radiation. Due to polarization transfer, the polarization of the fluorescence radiation significantly changes. Our present results are in agreement with other theoretical and experimental values.</p>