The article investigates the effect of diffusion plasma exposure time (30 s, 60 s) on the physicochemical properties of the surface of a natural rubber-based composite. X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) with dispersive X-ray spectroscopy (EDS) were used to assess the properties. Wettability and surface free energy tests were also performed. The application of plasma leads to surface oxidation (EDS). The obtained properties did not change for 21 days, and the plasma exposure time had no significant effect on the physicochemical changes of the composite surface.