<p>The excitation conditions and spectra signatures of surface phonon polaritons and plasmon–phonon polaritons in ZnO and Mn-doped ZnO ceramics have been theoretically analyzed and experimentally probed. Specular infrared reflection and attenuated total reflection spectroscopy were employed to investigate their dispersion relations. A single-oscillator model was used to describe the dielectric permittivity of ZnO ceramics, accounting for additive phonon and plasmon contributions. Theoretical and experimental dispersion curves were examined in the 100–4000&#xa0;cm⁻¹ and 240–4000&#xa0;cm⁻¹ spectral range, respectively. Additionally, the effect of an external magnetic field on surface polaritons was explored, revealing magnetically tunable optical responses. These findings contribute to the development of ZnO-based plasmonic and photonic devices, particularly in infrared and terahertz applications.</p>