We have analyzed and demonstrated surface-wave excitations, by propagating waves in air, at the interface between a truncated photonic crystal (PC) and a silver film in the near-infrared. The truncated PC was fabricated with several unit cells of alternating $\mathrm{Si}{\mathrm{O}}_2$ and ${\mathrm{Si}}_3{\mathrm{N}}_4$ layers. The dispersion relation of surface waves was calculated using the supercell method. A Fourier-transform infrared spectrometer measured the spectral reflectance of the fabricated sample at different incidence angles. An angle-resolved laser scatterometer measured the reflectance as a function of the incidence angle at the wavelength of $891\mathrm{nm}$ . The agreement between the resonance conditions obtained from experiments and the calculated dispersion relation manifests that surface waves at the PC–Ag interface may be utilized to build coherent thermal-emission sources.