In this study, variable-temperature grazing-incidence X-ray diffraction, transmission electron and scanning force microscopy were employed to address the semicrystalline structure and surface morphology of thin poly(p-xylylene) – silver nanocomposite films with Ag concentrations up to 12 vol.%. It was observed that the dominant crystalline modification of poly(p-xylylene) in the studied films is α-form, which is in contrast to thick poly(p-xylylene) films deposited at liquid nitrogen temperature where β-form prevails. The films exhibit planar texture that can be further enhanced on annealing. The optical properties of the films were studied by UV–vis and IR-spectroscopy. It was found that the samples display surface plasmon resonance, with the peak wavelength in the range of 435–445 nm. The peak positions undergo a redshift upon a long-term storage under ambient conditions. The IR-spectroscopy reveals the bands, which can be assigned to the vibrations of oxygen-containing groups, with intensity increasing with silver content. Display omitted •Thin PPX-Ag nanocomposite films were synthesized by low-temperature VDP.•PPX crystallizes in unusual at such low deposition temperatures α-form.•The films exhibit planar texture that can be further enhanced on annealing.•The samples display surface plasmon resonance with the maximum in the range of 435–445 nm.•The correlation between the structure and optical properties was explored.