An experimental investigation of the Cs $6s\phantom{\rule{0.2em}{0ex}}^{2}S_{1∕2}\ensuremath{\rightarrow}6p\phantom{\rule{0.2em}{0ex}}^{2}P_{3∕2}\ensuremath{\rightarrow}10s\phantom{\rule{0.2em}{0ex}}^{2}S_{1∕2}$ double-resonance two-photon polarization spectrum has been made. In the investigation, a linear polarization degree was measured to extract the alignment depolarization cross section in the cesium $6p\phantom{\rule{0.2em}{0ex}}^{2}P_{3∕2}$ level due to collisions between ground-level argon and excited $6p\phantom{\rule{0.2em}{0ex}}^{2}P_{3∕2}$ cesium atoms over the Zeeman coherences. The spectra show strong depolarization of the Cs $6p\phantom{\rule{0.2em}{0ex}}^{2}P_{3∕2}$ level. The measured alignment depolarization cross section value of 186 $(58)\phantom{\rule{0.3em}{0ex}}{\mathrm{\AA{}}}^{2}$ is in good agreement with the experiment and theoretical predictions.